use gradle 0.12 so the project will open into AS

Hopefully nobody is stuck on 0.11.
Fix #157 "Can't switch to any event year after..."

Fix #157 by updating the action bar's selected nav item when the user
selects an item.

But I'm puzzled as to why ViewTeamActivity#onNavigationItemSelected()
doesn't have the same bug. Does one of its listeners recreate the menu?
Revert "Fix #157 "Can't switch to any event year after...""

This reverts commit 7dfc9b9454b9c283ddbb393c265f689119d6c910.

Moved this commit to branch fix_157 for a separate pull request.
Merge pull request #169 from 1fish2/master

use gradle 0.12 so the project will open into AS