diff --git a/demo/package-lock.json b/demo/package-lock.json
index 0c58d26..f4374ae 100644
--- a/demo/package-lock.json
+++ b/demo/package-lock.json
@@ -151,7 +151,7 @@
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@@ -979,7 +979,7 @@
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+      "resolved": "https://registry.npmjs.org/ajv/-/ajv-6.4.0.tgz",
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@@ -1250,7 +1250,7 @@
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+      "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
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-          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
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@@ -3866,18 +3866,32 @@
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+      "resolved": "https://registry.npmjs.org/elliptic/-/elliptic-6.5.4.tgz",
+      "integrity": "sha512-iLhC6ULemrljPZb+QutR5TQGB+pdW6KGD5RSegS+8sorOZT+rdQFbsQFJgvN3eRqNALqJer4oQ16YvJHlU8hzQ==",
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-        "brorand": "^1.0.1",
+        "bn.js": "^4.11.9",
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-        "inherits": "^2.0.1",
-        "minimalistic-assert": "^1.0.0",
-        "minimalistic-crypto-utils": "^1.0.0"
+        "hmac-drbg": "^1.0.1",
+        "inherits": "^2.0.4",
+        "minimalistic-assert": "^1.0.1",
+        "minimalistic-crypto-utils": "^1.0.1"
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+          "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-4.12.0.tgz",
+          "integrity": "sha512-c98Bf3tPniI+scsdk237ku1Dc3ujXQTSgyiPUDEOe7tRkhrqridvh8klBv0HCEso1OLOYcHuCv/cS6DNxKH+ZA==",
+          "dev": true
+        },
+        "inherits": {
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+          "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+          "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
+          "dev": true
+        }
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@@ -4466,7 +4480,7 @@
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@@ -4653,7 +4667,7 @@
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@@ -4770,7 +4784,7 @@
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-          "resolved": "http://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
+          "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
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@@ -4857,7 +4871,8 @@
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@@ -4878,12 +4893,14 @@
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+          "dev": true,
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@@ -5025,7 +5045,8 @@
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@@ -5037,6 +5058,7 @@
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@@ -5051,6 +5073,7 @@
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@@ -5058,12 +5081,14 @@
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           "version": "0.0.8",
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-          "dev": true
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+          "optional": true
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@@ -5082,6 +5107,7 @@
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@@ -5162,7 +5188,8 @@
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@@ -5174,6 +5201,7 @@
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@@ -5259,7 +5287,8 @@
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@@ -5295,6 +5324,7 @@
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@@ -5314,6 +5344,7 @@
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@@ -5357,12 +5388,14 @@
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+          "resolved": "https://registry.npmjs.org/yargs/-/yargs-1.2.6.tgz",
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@@ -6333,7 +6368,7 @@
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@@ -7362,7 +7397,7 @@
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