Shut Up GL Error

Fixes invalid keycodes logging obnoxious and constant messages:

########## GL ERROR ##########
@ Pre render
65539: Invalid key -1

I played on my modpack, where I have many unbound keys, for 3 hours and 4000 of these errors were logged.

The Solution

This mod simply patches the InputConstants#isKeyDown method to return false when the keycode is -1 or 0. There was never a real error going on here - not the kind you should have to worry about and definitely not the kind that should pollute logs constantly.