Clean up code that redefines default leaves and default jungle leaves
(it was redefining more stuff than was necessary).  As a side effect,
this fixes a bug where non-plantlike leaves were using the wrong
textures in the inventory.

Remove all of the previous waving leaves changes as the shader that provides
that feature is about to change in a way that will break what I had here.

Clean up code that sets default drawtype and visual_scale of leaves