Added adbclient module.

- Updated doc
AndroidViewClient is now 100% python

- Version 4.0.0
- Kissed monkeyrunner goodbye
- Module private methods renamed (_)
- Added VIEW_CLIENT_TOUCH_WORKAROUND_ENABLED set to False
- Improved UTF-8 support for XML
- culebra: USE_JAR default value changed to False
Merge branch 'adbclient-implementation'