Androidport

Works of android port.

Notices.
1. added more native submodules - libpng, libfreetype2, libfontconfig, libexpat (currently, they are on our repo)
2. build directory change : <build directory>/<XXXX> -> <build dir>/<target triples>/<XXXX>
3. added android main
4. uses freeGLUT instead of GLFW on android
4. fixed misc.

Usage: configure --target-triples=arm-linux-androideabi && make
Result: cross-compiled 32-bit so libraries.