New Central Command, based off of Bay's

* Fixes wizard door wand exploit in a very fun way with step_trigger/teleport into singularity.
* Adds bay's shuttle windows.  They're exactly the same as reinforced windows in terms of health.
* (A lot of) Centcom's machines there are not actually machines.  They're actually structures that look like machines, to reduce lag.
* Much of the structure is old centcom, but moved around.  Embellishments and artistic license has also been used heavily so it's somewhat unique.  Somwhat.
* Stairs actually work (hint: it's not the stairs, it's the step_trigger)
* Airlocks are compliant with different access levels for centcom (101-107, 109)
* Adds some misc things for admins to play with, like a huge plane with a turf not used anywhere else (I think) for easy mass-varedit, a premade, but empty 'dungeon' area linked to centcom, and a 'fleet' of ships (we need more ships, submit yours!)
* Adds myself to admins.txt because forgetting to do it every time is annoying.
* Also stole bay's beach sprites and added it to holodeck and bar.

* Adds a "secret" on the second floor.  Credit goes to Mechoid for the sprite.

Tour of new Centcom (HUGE FILE)
http://puu.sh/9ZcPU/61177623a1.gif

And yes, I did use map merge tool.

Poll: http://tgstation13.org/phpBB/viewtopic.php?f=16&t=891