nitg: intro the platform concept

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
android: adds support for the android platform

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: minimal test for compilation to android

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: skip android related test in niti

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>