Added webpack.ProvidePlugin for most used imports

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

app/javascript/gabsocial/components/display_name.js

@@ -1,6 +1,4 @@
-import React from 'react';
 import ImmutablePropTypes from 'react-immutable-proptypes';
-import PropTypes from 'prop-types';
 import VerificationBadge from './verification_badge';
 
 export default class DisplayName extends React.PureComponent {