Map Fixes 12

[DESTROYGIRL]

(Dis)engage:

• Made the prop table still
• Made 1 decal not appear where it shouldnt

Marketa:

• Made many physics props debris
• Made some physics props stationary
• Various other optimisations

Rogue:

• Removed the girder in tank warehouse that appeared in competitive mode
• Changed some clips so you can't pixel walk on them

Transit:

• Clipped stairs at spawn

[sunzenshen]

Confirmed that clipping the stairs in transit really helped bot navigation:

bot-transit-clipped-stairs-autogen.mp4

That said for my peace of mind, I think I'm going to go manually create smooth stair NavAreas in #104 just to be sure. (That doesn't block this PR, in fact I want this PR to go in so that I can just keep the tweak in #104)