Added a small alcove in Engineering Maint

As requested by Cheridan
[CHANGELOG] for #3323
Merge pull request #3387 from Ikarrus/clog3323

[CHANGELOG] for #3323
Merge pull request #3370 from Ikarrus/maintalcove

Added a small alcove in Engineering Maint
Merge branch 'master' of git://github.com/tgstation/-tg-station

Conflicts:
	_maps/map_files/tgstation.2.1.3.dmm