Move event types to base backend

src/backends/base.js

@@ -13,7 +13,14 @@
  * limitations under the License.
  */
 
+const eventNamespace = 'team.auglement.augmentile';
+const EventTypes = {
+  map: eventNamespace + '.map',
+  player: eventNamespace + '.player'
+};
+
 class BaseBackend {
 }
 
 export default BaseBackend;
+export { EventTypes };

src/backends/widget.js

@@ -13,15 +13,9 @@
  * limitations under the License.
  */
 
-import BaseBackend from './base';
+import { BaseBackend, EventTypes } from './base';
 import WidgetApi from 'matrix-widget-api';
 
-const eventNamespace = 'team.auglement.augmentile';
-const EventTypes = {
-  map: eventNamespace + '.map',
-  player: eventNamespace + '.player'
-}
-
 class WidgetBackend extends BaseBackend {
   constructor(widgetId, userId) {
     this.api = new WidgetApi(widgetId);