Minor mapping tweaks

Just a couple of things mentioned in "The Little Things" thread.

http://baystation12.net/forums/viewtopic.php?p=200105#p200105
Gave engine room airlock camera x-ray upgrade (so AI can see SMES).

http://baystation12.net/forums/viewtopic.php?p=198186#p198186
Locked engine room core access doors. (Because I've accidentally bumped these open too)