Add missing dev deps and add editorconfig

Author: Rouven Bühlmann

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[{.*rc,.*rc.js,dreiup-settings.json,package.json,package-lock.json,.travis.yml}]
+indent_style = space
+indent_size = 2
+insert_final_newline = false
+
+[{package.json,package-lock.json}]
+insert_final_newline = true

package.json

@@ -31,8 +31,12 @@
   },
   "homepage": "https://github.com/biancojs/viewport#readme",
   "devDependencies": {
+    "@gianlucaguarini/eslint-config": "^1.0.0",
+    "eslint": "^4.4.0",
     "jsdom": "9.5.0",
     "jsdom-global": "2.1.0",
+    "mocha": "^4.0.1",
+    "rollup": "^0.52.0",
     "rollup-plugin-node-resolve": "^2.0.0"
   }
 }

rollup.config.js

@@ -1,16 +1,16 @@
 import resolve from 'rollup-plugin-node-resolve'
 
 export default {
-  entry: 'index.next.js',
+  input: 'index.next.js',
   plugins: [
     resolve({
       jsnext: true
     })
   ],
-  targets: [
+  output: [
     {
-      dest: 'index.js',
+      file: 'index.js',
       format: 'cjs'
     }
   ]
-}
+}