Show a spinner if creating a room on "Start chat" click

Use a gif instead of 'orrible CSS spinners which are CPU hungry. Encapsulate
it in a very basic Spinner atom.

src/skins/vector/css/common.css

@@ -86,6 +86,10 @@ a:visited {
     cursor: pointer;
 }
 
+.mx_ContextualMenu_spinner {
+    display: block;
+    margin: 0 auto;
+}
 
 .mx_Dialog_background {
     position: fixed;

src/skins/vector/views/atoms/Spinner.js

@@ -0,0 +1,34 @@
+/*
+Copyright 2015 OpenMarket Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+'use strict';
+
+var React = require('react');
+
+module.exports = React.createClass({
+    displayName: 'Spinner',
+
+    render: function() {
+        var w = this.props.w || 32;
+        var h = this.props.h || 32;
+        var imgClass = this.props.imgClassName || "";
+        return (
+            <div>
+                <img src="img/spinner.gif" width={w} height={h} className={imgClass}/>
+            </div>
+        );
+    }
+});

src/skins/vector/views/molecules/MemberInfo.js

@@ -17,6 +17,7 @@ limitations under the License.
 'use strict';
 
 var React = require('react');
+var Loader = require("../atoms/Spinner");
 
 var MatrixClientPeg = require('matrix-react-sdk/lib/MatrixClientPeg');
 var MemberInfoController = require('matrix-react-sdk/lib/controllers/molecules/MemberInfo')
@@ -26,7 +27,7 @@ module.exports = React.createClass({
     mixins: [MemberInfoController],
 
     render: function() {
-        var interactButton, kickButton, banButton, muteButton, giveModButton;
+        var interactButton, kickButton, banButton, muteButton, giveModButton, spinner;
         if (this.props.member.userId === MatrixClientPeg.get().credentials.userId) {
             interactButton = <div className="mx_ContextualMenu_field" onClick={this.onLeaveClick}>Leave room</div>;
         }
@@ -34,6 +35,10 @@ module.exports = React.createClass({
             interactButton = <div className="mx_ContextualMenu_field" onClick={this.onChatClick}>Start chat</div>;
         }
 
+        if (this.state.creatingRoom) {
+            spinner = <Loader imgClassName="mx_ContextualMenu_spinner"/>;
+        }
+
         if (this.state.can.kick) {
             kickButton = <div className="mx_ContextualMenu_field" onClick={this.onKick}>
                 Kick
@@ -64,6 +69,7 @@ module.exports = React.createClass({
                 {kickButton}
                 {banButton}
                 {giveModButton}
+                {spinner}
             </div>
         );
     }