AuraStorage now completely asynchronous using Promises.

Aura team code review feedback.

Fix AuraClientServiceTest so that it can use Promises correctly.

Feedback from Gerald Torres

Theoretical fix to webSQLAdapterTest.testClear. (Theoretical because I can't repro)

Theoretical fix to webSQLAdapterTest.testClear - db now used asynchronously. Not sure it worked before, because it's always been async, but was called as if it were synchronous. (Theoretical because I can't repro)
Merging origin/tmoss/master-pending-asyncstorage-PR into master