Fixes for Android build errors. Enable sensor landscape rotation.

Fix typo in Android Makefile ndk path.
Fix touchscreen parts of game.cpp to work after Zeno's refactor.
Fix isdigit and isspace overload conflict with Android Irrlicht in string.h
Enable sensor landscape rotation in Android Manifiest.
Add mapgen v5 to Android build.
Fix Makefile not checking leveldb.

Signed-off-by: Craig Robbins <kde.psych@gmail.com>