Prepare for release 1.1.0.
Merge branch 'release-1.1.0' into develop

* release-1.1.0:
  Prepare for release 1.1.0.
  Prepare for release 1.1.0-beta-6.
  Use Crashlytics instead of ACRA.
  Handle service NPEs in RandomPlayActivity.
  Propogate the return value from changeVolumeBy().
  Verify that the return from getService() is not null.
  Start handling a nullable service binding in NowPlayingFragment.
  Ensure that activity options menu items reflect the bound service state.
  Fix NPEs with the service connection in *ListActivity::orderPage().
  Fix the REORDER_TO_FRONT 4.4.2 problem
  Avoid NPEs when registering callbacks.
  WIP: Rename "service" to "mService".
  WIP: Fix NPEs involving the bound service.
  Add a feature graphic, which is now a requirement for Google Play.
  Fix an NPE in updatePlayerDropDown().
  Prepare the release for 1.1.0-beta-5.
  Use an explicit version of Gradle to ensure reproducibility.
  Add downloaded files to the media library.
Fix NPE when opening MusicFolderListActivity.

Options menu items only exist if mFolder != null.
Prepare for release 1.1.1.
Merge branch 'release-1.1.1' into develop

* release-1.1.1:
  Prepare for release 1.1.1.
Merge remote-tracking branch 'origin/develop' into player-groups