Increases android.py coverage from 24% to 36% and total coverage from
25% to 29%.
Note that this tests would have caught the glob issue reported in #1044.
This is a best effort approach trying to increase the coverage of that
module. Therefore some tests are not completely isolating all
dependencies via `mock.patch`-ing.
Subsequent pull request could cover more methods and focus on edge case.
This increases the overall coverage from 20% to 25% and
`buildozer/targets/android.py` coverage from 15% to `24%`.
