fix(keyboard-bindings): prevent actions that we handle

We previously did not properly silence further processing of
keyboard shortcuts, leading to `r` to trigger the original behavior.

Closes #203

lib/features/keyboard-bindings/KeyboardBindings.js

@@ -55,7 +55,7 @@ export default function KeyboardBindings(eventBus, injector) {
     keyboard.addListener(VERY_HIGH_PRIORITY, function(event) {
       var keyEvent = event.keyEvent;
 
-      handleKeyEvent(keyEvent);
+      return handleKeyEvent(keyEvent);
     });
 
   });