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/notifications/containers/notification_container.js

@@ -1,4 +1,3 @@
-import { connect } from 'react-redux';
 import { makeGetNotification, makeGetStatus } from '../../../selectors';
 import Notification from '../components/notification';
 import { openModal } from '../../../actions/modal';