Added catwalks and railings. Ported from Vorestation who ported them from Eris.
Note, catwalks can be placed on plating (as is seen on the vorestation map Tether) and is done so here as well. However it doesn't seem like it is possible to build said catwalks on plating. Did not bother to adjust this at this time. Something to sort in the future.
Adjusted SC station dmm to use both the railing and catwalks as well as a couple fixes for the floor tile adjustment in a earlier commit.
Things that are not on the turf floor should no longer drop through catwalks. YOU CAN NOW SAFELY BAG YOUR CRAP WITHOUT LOSING IT TO THE VOID THAT IS THE FLOOR DOWNSTAIRS.
* Lattices no longer block all downward movement out of their turf, they only block downward falling out of their turf.
* Objects are once again pullable on catwalks (not 100% sure why they were not, but had to do with the falling code calling Move())
* Falling on top of a mob will no longer do an infinate loop of swapping places vertically.
* Fix falling to check if movement actually succeeds before taking damage from falling.
* De-snowflakes how objects prevent you from falling out of their turf (catwalks and latticue)
* Improved the messaging and the way falling procs are called to make it more flexible and possible to hit things in a turf before the turf itself.
* Catwalks are an upgrade to lattice; instead of just a framework of wires its a mostly solid grid walkway.
* They are semi-transparent so you can see wires/pipes below them a bit.
* Smoothly auto-joining sprites to look proper.
* Constructed by upgrading lattice; like lattice it will stop you falling if build over an open space.
* Changes from Eris: Converted << to to_chat(), fix redraw on Destroy(), Fix color macros in text.
