Add basic unit tests with avoriaz

package.json

@@ -30,6 +30,7 @@
   },
   "devDependencies": {
     "autoprefixer": "^6.7.2",
+    "avoriaz": "^4.1.0",
     "babel-core": "^6.22.1",
     "babel-eslint": "^7.1.1",
     "babel-loader": "^6.2.10",
@@ -44,7 +45,7 @@
     "chromedriver": "^2.27.2",
     "connect-history-api-fallback": "^1.3.0",
     "copy-webpack-plugin": "^4.0.1",
-    "cross-env": "^3.1.4",
+    "cross-env": "^5.0.5",
     "cross-spawn": "^5.0.1",
     "css-loader": "^0.26.1",
     "eslint": "^3.14.1",
@@ -84,7 +85,7 @@
     "selenium-server": "^3.0.1",
     "semver": "^5.3.0",
     "shelljs": "^0.7.6",
-    "sinon": "^2.1.0",
+    "sinon": "^3.2.1",
     "sinon-chai": "^2.8.0",
     "stats-webpack-plugin": "^0.6.0",
     "url-loader": "^0.5.8",