Inverting axises

Cool library, but one thing I couldn't easily figure out how to do with the remapping was to invert axises. On Android 11, some bluetooth controllers such as the Nimbus which is designed for iOS have inverted y-axis on the analog stick. It would be nice to be able to invert the axis with remapping.

Start by locating the remapping implementation and the Android controller-axis input handling described in the issue. Check how analog-stick axes are represented and where remapped values are applied; done means remapping can invert an axis, including the y-axis, for affected Bluetooth controllers.

Written by the indexing model from the issue text.