This adds:
- mossy stone brick stairs
- mossy cobblestone stairs
- mossy stone brick walls
We also add another block class for walls, and while we're at it,
clean up the stairs texture function to not have a huge sprawling
elif mess for loading textures, but instead to a cheeky dictionary
lookup.
In case you're wondering, yes I am just as disgusted by this code as
you are.
Sorry for the noise in mc_id.h, but somebody decided they want DOS
line endings and I couldn't allow that to happen. When not doing that
put the whole thing into diff, I decided to just fix the indentation
too while I was at it.
Needed bugfixing of some overlooked unsigned char usages for block IDs,
as otherwise the lighting would be scuffed.
Concerns issue #1486.
