Have separate DEPOT_SEEDS[] array instead of having 'free' seeds at top of map.
Define the fields of the 'AREA' structure.
1. compute 'svolume' of each area / room
2. reworked dummy build code to be area based (not room based)
Partial work on algorithm to void-up some areas, making sure that we
don't cut-off areas in the process.
Find the neighbor areas for each area.
Finished the Weird_void_some_areas() code and fixed several bugs.