android_mnit: free textures from main memory after loading in GPU memory

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/jvm: fix returns from C implementations

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/string: allocate enough memory for '\0' in `String::native_int_to_s`

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