Remove React, PureComponent global import, added those imports to files directly

• Remove:
- React, PureComponent global import and added those imports to files directly

app/javascript/gabsocial/containers/display.js

@@ -1,3 +1,4 @@
+import React from 'react'
 import {
   FONT_SIZES,
   THEMES,
@@ -5,7 +6,7 @@ import {
   DEFAULT_FONT_SIZE,
 } from '../constants'
 
-class Display extends PureComponent {
+class Display extends React.PureComponent {
 
   state = {
     theme: this.props.theme,

app/javascript/gabsocial/containers/gabsocial.js

@@ -1,5 +1,6 @@
 'use strict'
 
+import React from 'react'
 import { Provider } from 'react-redux'
 import configureStore from '../store/configureStore'
 import { BrowserRouter, Route } from 'react-router-dom'
@@ -36,7 +37,7 @@ const mapStateToProps = (state) => ({
 })
 
 @connect(mapStateToProps)
-class GabSocialMount extends PureComponent {
+class GabSocialMount extends React.PureComponent {
 
   static propTypes = {
     shownOnboarding: PropTypes.bool.isRequired,
@@ -80,7 +81,7 @@ class GabSocialMount extends PureComponent {
 
 }
 
-export default class GabSocial extends PureComponent {
+export default class GabSocial extends React.PureComponent {
 
   static propTypes = {
     locale: PropTypes.string.isRequired,

app/javascript/gabsocial/containers/media_container.js

@@ -1,4 +1,4 @@
-import React, { PureComponent, Fragment } from 'react';
+import React from 'react';
 import ReactDOM from 'react-dom';
 import PropTypes from 'prop-types';
 import { IntlProvider, addLocaleData } from 'react-intl';
@@ -14,7 +14,7 @@ addLocaleData(localeData);
 
 const MEDIA_COMPONENTS = { MediaGallery, Video, Card, Poll };
 
-export default class MediaContainer extends PureComponent {
+export default class MediaContainer extends React.PureComponent {
 
   static propTypes = {
     locale: PropTypes.string.isRequired,
@@ -49,7 +49,7 @@ export default class MediaContainer extends PureComponent {
 
     return (
       <IntlProvider locale={locale} messages={messages}>
-        <Fragment>
+        <React.Fragment>
           {[].map.call(components, (component, i) => {
             const componentName = component.getAttribute('data-component');
             const Component = MEDIA_COMPONENTS[componentName];
@@ -72,7 +72,7 @@ export default class MediaContainer extends PureComponent {
               component,
             );
           })}
-        </Fragment>
+        </React.Fragment>
       </IntlProvider>
     );
   }

app/javascript/gabsocial/containers/notification_container.js

@@ -1,3 +1,4 @@
+import React from 'react'
 import { List as ImmutableList } from 'immutable'
 import { makeGetNotification } from '../selectors'
 import Notification from '../components/notification'

app/javascript/gabsocial/containers/status_container.js

@@ -1,3 +1,4 @@
+import React from 'react'
 import { FormattedMessage } from 'react-intl'
 import {
   Map as ImmutableMap,