Update more packages

[amyspark]

This is the last round of upgradable, drop-in Node packages.

The remaining ones are:

amalia@Sakura:~/Desktop/whalebird$ npm outdated
Package             Current   Wanted  Latest  Location
babel-loader          7.1.5    7.1.5   8.0.4  Whalebird
css-loader          0.28.11  0.28.11   1.0.1  Whalebird
electron              3.0.8    3.0.8  3.0.10  Whalebird
electron-packager    12.2.0   12.2.0  13.0.0  Whalebird
eslint-plugin-html    4.0.6    4.0.6   5.0.0  Whalebird

babel-loader rejects the current structure of .eslintrc.js. css-loader 1.0.1 removes the PostCSS minifier, which must be added manually to the pipeline. electron and electron-packager I've left them as is (#712), and eslint-plugin-html requires eslint-plugin-vue. The latter package will require a whole lot of style changes to Whalebird's source.