Android: Report api level of unknown android versions

Change-Id: I5893b5e9ec57da68dc09d0c10a8a43dc074cdd73
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Android: Support Android-L with a hack

android list avd outputs "Target: Android L (Preview) (API level L)",
which we treat as API Level 20 now.

Change-Id: Idc74fc833ffd69959af9d25cdaaa115f35c06831
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
androidNameForApiLevel: Api-Level 20 is Android L

That's unlikely to be the final name, but introduce it for now.

Change-Id: Iaf1fd65e797a2354433b9bb5af6a6d76ecb8409c
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>