Tel Test Script: Remove temp hack for VT test. Add Setting test case.

1. Remove temporary hack for VT tests.
2. Add SL4A APIs to bring inCallUI to foreground and show home screen.
3. Bring inCallUI to foreground after answer call.
4. Add VT setting test case.
5. Update VT test suite.

Change-Id: I0bdd42d43ca9428c1ddf30d9e85e353b11c92f82
2 files changed