[Mobile-sig] support of the android platform

[Xavier de Gaye]

Starting with API level 21 (Android 5.0), the build of python3 with the
official android toolchains (that is, without resorting to external libraries
for wide character support) runs correctly.  With the set of patches described
in the patches/Makefile file at [1], the cpython test suite runs[2] on the
android x86 and armv7 emulators with only few errors[3].  Those errors are
listed with their corresponding error messages, this may give a raw idea of
the effort needed to support this platform.

This post has been first submitted to python-dev as:
https://mail.python.org/pipermail/python-dev/2016-April/144320.html

Xavier

[1] https://bitbucket.org/xdegaye/pyona/src
[2] To reproduce these results, follow the instructions found in INSTALL
     at https://bitbucket.org/xdegaye/pyona/wiki/install
[3] https://bitbucket.org/xdegaye/pyona/wiki/testsuite