Mech fabricator fix

Mech fabs were looking in their lighting sub-area to connect to equipment in their logical area; if the mech fab and the R&D computer were at different lighting levels, they would cease to be in the same area, making them fail to connect.

This adds a global helper proc to return the contents of a logical area rather than the lighting sub-area, adds that functionality to the mech fab, and makes failing to connect to an R&D computer a recoverable error.