Added webpack.ProvidePlugin for most used imports

Removed imports of React, connect, PropTypes throughout
Removed the "React" in React.Component/PureComponent

app/javascript/gabsocial/features/ui/components/bundle.js

@@ -1,10 +1,8 @@
-import React from 'react';
-import PropTypes from 'prop-types';
 
 const emptyComponent = () => null;
 const noop = () => { };
 
-class Bundle extends React.PureComponent {
+class Bundle extends PureComponent {
 
   static propTypes = {
     fetchComponent: PropTypes.func.isRequired,