some work done on import-unit

compiles, doesn’t produce any usable results
IO Unit is now functioning for import & export

however, claw-movement and some sanity-checks are still missing
more work done on IO Unit

BUG: claw flickers if idle and has been moved before
fixes claw-flickering

however, claw will close completely even for bigger objects >:-|
fixed: claw-closing, multiple items on import

BUG: using air while waiting for items
Better reset handling
more refactoring

seems mostly harmless^Wstable
some cleanup work
Merge pull request #1 from DarkStarDS9/shelf

refactoring for IOUnit done; also refactored some related parts