Androidviewclient

This **BETA** release includes major changes
- Support for python 2.7 and python 3.6+
- Support for new [CulebraTester2-public](https://github.com/dtmilano/CulebraTester2-public) backend using [CulebraTester2-client](https://github.com/dtmilano/CulebraTester2-client)

This **BETA** release includes major changes
- Support for python 2.7 and python 3.6+
- Support for new [CulebraTester2-public](https://github.com/dtmilano/CulebraTester2-public) backend using [CulebraTester2-client](https://github.com/dtmilano/CulebraTester2-client)

- adbclient: changed drag() duration parameter units
- Optional parameter serialno to AdbClient
- Added scripts to distrivution
- Added write-image-to-file.py example
- Corrected image cropping coordinates
- culebra: fixed indentation of generated script
- culebra: Added support for automatic unittest generation
- Issue 72: view.type(str) too slow
- Fixed according to gdobra suggestion
- Make AdbClient.getRestrictedScreen() public
- As suggested by elbajo
- Fixed Issue 67: Runaway Timer
- Solution provided by sk87287
- Check for invalid alpha specification for 32bpp
- AdbClient.unlock() screen method added
- Fixed typo in AdbClient.isLocked()

- AdbClient: Added `isLocked()` method to check if screen is locked
- Fixed 55: drag doesn't work for old Android versions
- Removed `sys.path` manipulation not needed for python
- Read `ANDROID_ADB_SERVER_PORT` environment variable to set adb PORT. This variable is set by Jenkins Android Emulator plugin.
- Merge pull request 56 from knorrium/clean-whitespaces
- Check for sys.executable that may be not available on Windows
- Examples modified to use python
- Marked jar file creation as deprecated
- Improved UTF-8 treatment in messages
- `AdbClient.startActivity()` raises exception on errors
- Warns if modules are imported using 'monkeyrunner'
- Added image comparison
- Decode used only on python's 8-bit strings
- Restored `obtainAdbPath()` used for android API <= 16
- Trap exception generated by integer division by zero in `takeSnapshot()`
- Fixed famebuffer exception