chore(test): add source map support for mocha

mocha-webpack.opts

@@ -1,2 +1,3 @@
 --colors
 --webpack-config webpack/test.js
+--require source-map-support/register

package.json

@@ -72,6 +72,7 @@
     "redux-devtools-filterable-log-monitor": "^0.6.6",
     "redux-mock-store": "^1.1.1",
     "sass-loader": "^4.0.0",
+    "source-map-support": "^0.4.2",
     "wallaby-webpack": "0.0.22",
     "webpack-dev-server": "^1.14.0",
     "webpack-merge": "^0.14.0",

webpack/base.js

@@ -3,7 +3,7 @@ const webpack = require('webpack');
 const CopyWebpackPlugin = require('copy-webpack-plugin');
 
 module.exports = {
-  devtool: 'inline-source-map',
+  devtool: 'source-map',
   entry: [
     'babel-polyfill',
     './app/index.jsx',