fixed <=0 errors in some tfx, added some new ones

Conflicts:
	nodes/texture11/Filter/TriColor (DX11.TextureFX) help.v4p
	nodes/texture11/Filter/TriColor.tfx
	nodes/texture11/Source/Gradient (DX11.TextureFX) help.v4p
	nodes/texture11/Source/Gradient.tfx

Cherry pick for commit on lost changes