Move dispatcher into a subdirectory

We're expecting to have a whole bunch of types for the dispatched payloads, so pull the thing into a directory we can throw them in.

src/components/views/right_panel/HeaderButtons.js

@@ -19,7 +19,7 @@ limitations under the License.
 */
 
 import React from 'react';
-import dis from '../../../dispatcher';
+import dis from '../../../dispatcher/dispatcher';
 import RightPanelStore from "../../../stores/RightPanelStore";
 
 export const HEADER_KIND_ROOM = "room";