tree bug fixed, random tree height

Please see the comments in blocks.py concerning the textures used.
names assigned to blocks, from boksee.
Fixed inventory GUI.
Merge commit '2320471b13b895db495e08315be2249bedf0ed83'

Conflicts:
	TODO.md
	blocks.py
	gui.py
	inventory.py
	main.py
Merge branch 'master' of git://github.com/avelanarius/Minecraft