Added GPLv3 license. In the great words of /u/Gavekort:

	Freedom 0: The freedom to eat the cake for any purpose.
	Freedom 1: The freedom to study how the cake is made, and change it to make it taste what you wish.
	Freedom 2: The freedom to redistribute pieces so you can help your neighbor.
	Freedom 3: The freedom to improve the cake, and release your improvements (and modified versions in general) to the public, so that the whole community benefits.