Fix Android build

It would be nice to fix android build and get the game working on Android again, todo:

• write android makefiles for libRocket, freetype, etc. i.e. all the stuff that was added after Android build got broken
• make sure touchscreen controller code still works... (it should)
• make LuaJIT compile for Android (particularly important for performance reasons)
• anything else ???

If everything is open-source, and if the build isn't too complicated, we could add it to F-Droid! :)

Yes, everything is open-source, the build shouldn't be too complicated, i.e. it's a matter of writing makefiles and m.b. fixing some platform-specific stuff. I would do it myself, but I don't have much free time and even when I have I'm working on a new game of mine :)