Incorrect Texture Mapping on Some Blocks

The texture mapping for these model types is incorrect:

• glass panes: See stained_pane_shaded.png and normal_pane_shaded
• iron bars: The 2*16px vertical texture on the iron bar when it is not connected is different than when it is connected; happens facing all 4 directions, but the texture change is different

all of these can take from the default generated UV mappings.