-Made it so that the registerload / registersave functions are only used if registerload exists. I'll presume there is no emulator that supports one and not the other. This will allow VBA to use this script, although it'll be missing one of the better features until it supports this function.
-Made the number of controllers tracked configurable. VBA was counting everything twice when this was set to 2. It will still default to 2, but it'll be easier for people to modify this for VBA now.
-As Lua starts counting from 1, and there may be a slot 0, increment the slot before saving / loading, storing data for slot 0 in states[1]
-Prevented the script from loading non-existent data.
-Removed the space from the file name so that it is more consistent with the FCEUX Lua repository, which this script is now a member of. :)
-Added messages when you save or (fail to) load data to / from a state.
-Made it so the script displays the button counts when you save / load a state.