Not compatible with /tg/ repo

[Shuffl3]

tried to do a simple mapfix on /tg/s omegestation in fastdmm. Rotated a couple pipes, changed a couple thousand lines of code. Good chance I might be dumb though.

fastdmm:
http://i.imgur.com/k1Sj6R5.jpg
DM with /tg/mapmerge:
https://github.com/tgstation/tgstation/pull/23655/files

Also something related to compatibility, some server still use the built in z-levels and as far as I'm aware you can't switch between them.

[Shuffl3]

theres a spat of mapmerge fixes that came through across ftl13 and tg. Im not into it enough to say what got fixed, but it seems like they got fixed in different ways. Reverted and used tg's mapmerge and it worked fine.

[d34d10cc]

I'd say that either the tgm format has changed in the meantime or the map merge updates changed the format of the maps leading to FastDMM reverting them to the old format, causing such bug changes.

[monster860]

My other theory is that planes could have more effect on sorting than the top level type