Add CallHandler singleton and add CallView.

CallView is the container for either VideoViews or WaveformViews. All UI
elements listen for 'call_state' payloads and then call
CallHandler.getCall(roomId) to extract the current MatrixCall for that room.
We can't do this via stateful dispatches because dispatching does not preserve
ordering empirically (probably due to setTimeout).

skins/base/views/molecules/voip/CallView.js

@@ -0,0 +1,58 @@
+/*
+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');
+
+var MatrixClientPeg = require("../../../../../src/MatrixClientPeg");
+var ComponentBroker = require('../../../../../src/ComponentBroker');
+var CallViewController = require(
+    "../../../../../src/controllers/molecules/voip/CallView"
+);
+var VideoView = ComponentBroker.get('molecules/voip/VideoView');
+
+module.exports = React.createClass({
+    displayName: 'CallView',
+    mixins: [CallViewController],
+
+    getVideoView: function() {
+        return this.refs.video;
+    },
+
+    render: function(){
+        return (
+            <VideoView ref="video"/>
+        );
+        /*
+        if (this.state && this.state.call) {
+            if (this.state.call.type === "video") {
+                return (
+                    <VideoView ref="video"/>
+                );
+            }
+            else if (this.state.call.type === "voice") {
+                // <WaveformView /> in the future.
+                return (
+                    <div></div>
+                );
+            }
+        }
+        return (
+            <div></div>
+        ); */
+    }
+});