Bump dependencies, add missing typing libraries (#2753)

* Bump dependencies and add missing typing libraries

* Fix expose-loader breaking changes

* Expose jQuery using its own typings instead of ours

* Extend jQuery typings with our own custom $.fn helpers

* Use jQuery typings for Component's `this.$` attribute

* Format webpack config file

* Use Spin.js 3.1.0

js/webpack.config.js

@@ -3,7 +3,7 @@ const merge = require('webpack-merge');
 
 module.exports = merge(config(), {
   output: {
-    library: 'flarum.core'
+    library: 'flarum.core',
   },
 
   // temporary TS configuration