Android support

[YariKartoshe4ka]

See #95 issue for more information

Logs of tests (android 10, Samsung J4 2018, SM-J400F):

• Termux (v0.101):
  • Tox Python 2 and 3 (passed)
  • Self tests (__main__) (PATH brute, passed)
• Pydriod 3 (v4.01_arm):
  • Tox Python 3 (first fail, in /sdcard directory)
  • Tox Python 3 (second fail, in app_HOME directory, home directory of Pydroid)
  • Self tests (__main__) (PATH brute, passed)
• Pydroid 2 (v2.0_arm):
  • Self tests (__main__) (PATH brute, passed)
• Custom app built with P4A (v2020.06.02):
  • Self tests (__main__) (Via pyjnius, passed)
  • App source
  • .P4A configuration file
  • GZIPped APK