Android: Add minimal Java editing support

Indentation for blocks '{'. '}' and completion for keywords.

TODO: "New File" is missing,
TODO: probably needs some tweaks to the indentation.
Task-number: QTCREATORBUG-11220

Change-Id: I758b3815e47d1427d39c0248eb16e39ffb7a29fb
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>