1) some changes to main.ui, so that all of the menu actions show up on OS X.
2) change the key for the inputMap dictionary, so that an axis as well as a button can be mapped to the same id. This was the case on OS X with a generic 2-axis gamepad (both an axis and a button were mapped to id=4).
NOTE: only tested on OS X. These changes should not have any effect on Linux/Windows but should be tested on those platforms first.