diff --git a/package-lock.json b/package-lock.json
index 031ee8e..4c21632 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2330,7 +2330,8 @@
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       "resolved": "https://registry.npmjs.org/chownr/-/chownr-1.0.1.tgz",
-      "integrity": "sha1-4qdQQqlVGQi+vSW4Uj1fl2nXkYE="
+      "integrity": "sha1-4qdQQqlVGQi+vSW4Uj1fl2nXkYE=",
+      "optional": true
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@@ -3644,7 +3645,7 @@
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       "integrity": "sha1-AB3fgWKM0ecGElxxdvU8zsVdkY4=",
       "requires": {
-        "urijs": "1.19.0"
+        "urijs": "^1.16.1"
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@@ -4893,11 +4894,6 @@
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-      "integrity": "sha1-w8T2xmO5I0WamqKZEtLQMfFQf4Q="
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@@ -5047,7 +5043,8 @@
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-          "integrity": "sha1-qJS3XUvE9s1nnvMkSp/Y9Gri1Cg="
+          "integrity": "sha1-qJS3XUvE9s1nnvMkSp/Y9Gri1Cg=",
+          "optional": true
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@@ -5471,7 +5468,8 @@
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@@ -5514,7 +5512,8 @@
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@@ -5527,6 +5526,7 @@
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+          "optional": true,
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@@ -5534,6 +5534,7 @@
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           "bundled": true,
+          "optional": true,
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@@ -5541,6 +5542,7 @@
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@@ -5548,7 +5550,8 @@
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+          "bundled": true,
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@@ -5562,30 +5565,36 @@
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+          "bundled": true,
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           "bundled": true,
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+          "bundled": true,
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@@ -5620,7 +5629,8 @@
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@@ -5647,7 +5657,8 @@
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@@ -5666,11 +5677,13 @@
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@@ -5721,6 +5734,7 @@
         "glob": {
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           "bundled": true,
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@@ -5732,7 +5746,8 @@
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@@ -5756,6 +5771,7 @@
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           "bundled": true,
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             "cryptiles": "2.0.5",
@@ -5765,7 +5781,8 @@
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@@ -5780,6 +5797,7 @@
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@@ -5787,7 +5805,8 @@
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@@ -5797,6 +5816,7 @@
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           "bundled": true,
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@@ -5808,7 +5828,8 @@
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@@ -5871,11 +5892,13 @@
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@@ -5883,17 +5906,20 @@
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           "version": "3.0.4",
           "bundled": true,
+          "optional": true,
           "requires": {
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         "minimist": {
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@@ -5943,7 +5969,8 @@
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@@ -5958,6 +5985,7 @@
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@@ -5983,7 +6011,8 @@
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@@ -5992,7 +6021,8 @@
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@@ -6025,6 +6055,7 @@
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@@ -6067,13 +6098,15 @@
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@@ -6093,6 +6126,7 @@
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@@ -6123,6 +6157,7 @@
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@@ -6132,6 +6167,7 @@
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@@ -6144,6 +6180,7 @@
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@@ -6156,6 +6193,7 @@
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@@ -6205,7 +6243,8 @@
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@@ -6230,7 +6269,8 @@
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@@ -6494,12 +6534,12 @@
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+      "version": "1.0.18",
+      "resolved": "https://registry.npmjs.org/gatsby-plugin-offline/-/gatsby-plugin-offline-1.0.18.tgz",
+      "integrity": "sha1-LuKiTS9p/MQ6AVEy8HFBtpKVMY0=",
       "requires": {
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-        "sw-precache": "5.2.0"
+        "babel-runtime": "^6.26.0",
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@@ -13048,7 +13080,8 @@
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+      "optional": true
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@@ -13587,11 +13620,6 @@
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-          "integrity": "sha1-Z+LoY3lyFVMN/zGOW/nc6/1Hsho="
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-          "resolved": "https://registry.npmjs.org/widest-line/-/widest-line-1.0.0.tgz",
-          "integrity": "sha1-DAnIXCqUaD0Nfq+O4JfVZL8OEFw=",
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-          "integrity": "sha1-+Aek8LHZ6ROuekgRLmzDrxmRtF8=",
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-            "imurmurhash": "0.1.4",
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-          "resolved": "https://registry.npmjs.org/xdg-basedir/-/xdg-basedir-2.0.0.tgz",
-          "integrity": "sha1-7byQPMOF/ARSPZZqM1UEtVBNG9I=",
-          "requires": {
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+      "version": "5.2.1",
+      "resolved": "https://registry.npmjs.org/sw-precache/-/sw-precache-5.2.1.tgz",
+      "integrity": "sha512-8FAy+BP/FXE+ILfiVTt+GQJ6UEf4CVHD9OfhzH0JX+3zoy2uFk7Vn9EfXASOtVmmIVbL3jE/W8Z66VgPSZcMhw==",
+      "requires": {
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+        "es6-promise": "^4.0.5",
+        "glob": "^7.1.1",
+        "lodash.defaults": "^4.2.0",
+        "lodash.template": "^4.4.0",
+        "meow": "^3.7.0",
+        "mkdirp": "^0.5.1",
+        "pretty-bytes": "^4.0.2",
+        "sw-toolbox": "^3.4.0",
+        "update-notifier": "^2.3.0"
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     "sw-toolbox": {
@@ -14702,8 +14540,8 @@
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       "requires": {
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-        "serviceworker-cache-polyfill": "4.0.0"
+        "path-to-regexp": "^1.0.1",
+        "serviceworker-cache-polyfill": "^4.0.0"
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@@ -14806,6 +14644,7 @@
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+      "optional": true,
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@@ -15081,6 +14920,7 @@
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       "integrity": "sha1-XPne6D1rd4YcPWxE1ThZrterBHk=",
+      "optional": true,
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@@ -15093,6 +14933,7 @@
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           "integrity": "sha1-G8k2ueAvSmA/zCIuz3Yz0wuLk7E=",
+          "optional": true,
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@@ -15104,12 +14945,14 @@
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           "resolved": "https://registry.npmjs.org/semver/-/semver-4.3.6.tgz",
-          "integrity": "sha1-MAvG4OhjdPe6YQaLWx7NV/xlMto="
+          "integrity": "sha1-MAvG4OhjdPe6YQaLWx7NV/xlMto=",
+          "optional": true
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         "source-map": {
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           "integrity": "sha1-yLbBZ3l7pHQKjqMyUhYv8IWRsmY=",
+          "optional": true,
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@@ -15118,6 +14961,7 @@
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           "integrity": "sha1-6lo5AKHByyUJagrozFwrSxDe09w=",
+          "optional": true,
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@@ -15566,9 +15410,9 @@
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-      "resolved": "https://registry.npmjs.org/urijs/-/urijs-1.19.0.tgz",
-      "integrity": "sha512-Qs2odXn0hST5VSPVjpi73CMqtbAoanahaqWBujGU+IyMrMqpWcIhDewxQRhCkmqYxuyvICDcSuLdv2O7ncWBGw=="
+      "version": "1.19.1",
+      "resolved": "https://registry.npmjs.org/urijs/-/urijs-1.19.1.tgz",
+      "integrity": "sha512-xVrGVi94ueCJNrBSTjWqjvtgvl3cyOTThp2zaMaFNGp3F542TR6sM3f2o8RqZl+AwteClSVmoCyt0ka4RjQOQg=="
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diff --git a/package.json b/package.json
index 90b82f0..d61cc8b 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,7 @@
     "gatsby-link": "^1.6.34",
     "gatsby-plugin-feed": "^1.3.15",
     "gatsby-plugin-google-analytics": "^1.0.15",
-    "gatsby-plugin-offline": "^1.0.12",
+    "gatsby-plugin-offline": "^1.0.18",
     "gatsby-plugin-react-helmet": "^1.0.8",
     "gatsby-plugin-sharp": "^1.6.25",
     "gatsby-plugin-typography": "^1.7.10",