Remove use of deprecated React.PropTypes

Replace all uses of React.PropTypes with PropTypes and importing PropTypes from
'prop-types'.

src/components/views/voip/CallPreview.js

@@ -15,6 +15,7 @@ limitations under the License.
 */
 
 import React from 'react';
+import PropTypes from 'prop-types';
 import RoomViewStore from '../../../stores/RoomViewStore';
 import CallHandler from '../../../CallHandler';
 import dis from '../../../dispatcher';
@@ -27,7 +28,7 @@ module.exports = React.createClass({
         // A Conference Handler implementation
         // Must have a function signature:
         //  getConferenceCallForRoom(roomId: string): MatrixCall
-        ConferenceHandler: React.PropTypes.object,
+        ConferenceHandler: PropTypes.object,
     },
 
     getInitialState: function() {

src/components/views/voip/CallView.js

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 import React from 'react';
+import PropTypes from 'prop-types';
 import dis from '../../../dispatcher';
 import CallHandler from '../../../CallHandler';
 import sdk from '../../../index';
@@ -26,25 +27,25 @@ module.exports = React.createClass({
     propTypes: {
         // js-sdk room object. If set, we will only show calls for the given
         // room; if not, we will show any active call.
-        room: React.PropTypes.object,
+        room: PropTypes.object,
 
         // A Conference Handler implementation
         // Must have a function signature:
         //  getConferenceCallForRoom(roomId: string): MatrixCall
-        ConferenceHandler: React.PropTypes.object,
+        ConferenceHandler: PropTypes.object,
 
         // maxHeight style attribute for the video panel
-        maxVideoHeight: React.PropTypes.number,
+        maxVideoHeight: PropTypes.number,
 
         // a callback which is called when the user clicks on the video div
-        onClick: React.PropTypes.func,
+        onClick: PropTypes.func,
 
         // a callback which is called when the content in the callview changes
         // in a way that is likely to cause a resize.
-        onResize: React.PropTypes.func,
+        onResize: PropTypes.func,
 
         // render ongoing audio call details - useful when in LeftPanel
-        showVoice: React.PropTypes.bool,
+        showVoice: PropTypes.bool,
     },
 
     getInitialState: function() {

src/components/views/voip/IncomingCallBox.js

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 import React from 'react';
+import PropTypes from 'prop-types';
 import MatrixClientPeg from '../../../MatrixClientPeg';
 import dis from '../../../dispatcher';
 import { _t } from '../../../languageHandler';
@@ -22,7 +23,7 @@ module.exports = React.createClass({
     displayName: 'IncomingCallBox',
 
     propTypes: {
-        incomingCall: React.PropTypes.object,
+        incomingCall: PropTypes.object,
     },
 
     onAnswerClick: function() {

src/components/views/voip/VideoFeed.js

@@ -17,17 +17,18 @@ limitations under the License.
 'use strict';
 
 import React from 'react';
+import PropTypes from 'prop-types';
 
 module.exports = React.createClass({
     displayName: 'VideoFeed',
 
     propTypes: {
         // maxHeight style attribute for the video element
-        maxHeight: React.PropTypes.number,
+        maxHeight: PropTypes.number,
 
         // a callback which is called when the video element is resized
         // due to a change in video metadata
-        onResize: React.PropTypes.func,
+        onResize: PropTypes.func,
     },
 
     componentDidMount() {

src/components/views/voip/VideoView.js

@@ -18,6 +18,7 @@ limitations under the License.
 
 import React from 'react';
 import ReactDOM from 'react-dom';
+import PropTypes from 'prop-types';
 import classNames from 'classnames';
 
 import sdk from '../../../index';
@@ -30,14 +31,14 @@ module.exports = React.createClass({
 
     propTypes: {
         // maxHeight style attribute for the video element
-        maxHeight: React.PropTypes.number,
+        maxHeight: PropTypes.number,
 
         // a callback which is called when the user clicks on the video div
-        onClick: React.PropTypes.func,
+        onClick: PropTypes.func,
 
         // a callback which is called when the video element is resized due to
         // a change in video metadata
-        onResize: React.PropTypes.func,
+        onResize: PropTypes.func,
     },
 
     componentDidMount: function() {