I am looking for an addon that would let me remap my keyboard buttons... for instance: Make Numpad0 behave like a Control button. Currently I am using AutoHotKeys for this, but I'm not 100% sure I won't get banned for it, as its a 3rd party program and not a WoW addon.
Unfortunatly there is no in-game way of doing that, addon or otherwise.
I think blizzard do tolerate the likes of autohotkey in certain circumstances depending on quite what you are using it for, though you can always ask on the forums for clarification.
In this case you are simply providing more convenient bindings, and not in any way automating the game experience.