Test build: Android controller sticks and triggers

Test build, not a release. It's for trying the Android controller fixes in #17: analog sticks, analog triggers and hat d-pads, including the built-in controls of handhelds like the Retroid Pocket and AYN.

• It installs over Birdman64 1.5.0 as an update, so your saves are kept. If you have a different build installed and Android refuses the install, use Export save… in the pause menu first, then uninstall and reinstall.
• Controller test: open Settings › Controls and scroll to "Controller". It lists the controllers your device reports, and "Last input" shows each press as it reaches the game. If a button does nothing, please report what those two lines say, along with your device and its controller mode.
• Please also try: steering with the left stick, Z on LT, the C buttons on the right stick, the d-pad, and rebinding.

Updated: build 2 (controller status and the last-input line on the Controls page).
SHA-256: 880d7201bb6734c88742c85104ab654425fcef8142b5a1d17bc6e1ec944f77c4