Bug 880001 - Fix mozdevice sut_push.py test;r=wlach

Always wait for the full, multiple-line push command, since
sometimes it is received in one part and sometimes in two.
Bug 886540 - Re-enable mozdevice unit tests;r=jhammel
Bug 886882 - Bump mozdevice to 0.27
Bug 886608 - Add adb forward, remount and devices wrappers to dmADB, r=wlach
Update sphinx docs for newly added dmADB methods