Chaquopy: Python 2 for Android

May 30, 2018

Demo app:
* Make Python 3 the default flavor.
* Don't suppress keyboard predictions in ConsoleActivity base class.

SDK:
* Add support for installing pure-Python sdists.
* Fix imp.find_module and imp.load_module.
* Implement implicit namespace packages on Python 3 (PEP 420).
* Add partial support for .pth files.
* Add message explaining how to show full pip output in Android Studio 3.1’s new Build window.
* Fix “registering invalid inputs” warning in Android Studio 3.1.