feat: unified input system and input bindings

[lajbel]

2 problems, now you have to hardcode input keys, for example

onKeyPress("space");

And also you have to implement two handlers for controllers and keyboard compatibility

onKeyPress("space", jump);
onGamepadButtonPress("dpad-up", jump)

So Write spec

• [x] unified system of inputs: onButtonPress("jump")
• [x] methods for set and get input bindings getButton("jump"), getButtonByKey("up")
• [x] example