1.9.4 - small fixes and cleanup, removed drawPoly

• improve audio play on first click, prevents stacking while still allowing the first sound to go through
• added TileInfo.frame() function for cleaner animation code
• fix particle angle speed not working, it just wasn't hooked up, thanks to deep scan for helping me notice.
• clean up some minor issues so deep scan is 100% perfect.
• removed drawPoly, not needed by engine. feel free to copy that old function to your game code if you still need it.
• improve platformer example with better sprite atlas and level loading code
• improve touch gamepad, apply deadzone and fix issue with touchGamepadAnalog=0
• remove unused glPostArrayBuffer in webgl code