having a) monsters as treasures b) multipart monsters as treasures
and c) multipart monsters as terasures on tiled maps... hit a big
pile of bugs again.

this change:

- implements a per-map active flag. when items are being inserted
  they are activated or deactivated according to that flag.
  this could get rid of most or even all of the explicit
  activate/deactivate calls.
- implement some glue to make instantiating multipart objects easier
  (this is used inside fix_multipart_objects and might make it possible
  to put multipart objects at map borders - those were winged before)
- do finer-grained locking as to not lead to deadlocks when insert
  recurses e.g. when loading tiled maps.

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meet our new pod fucntionality, certainly not finished :) let me also introduce the beginnings of a new help command