v5.1.1

• 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()