Convert constants to class variables
Add errorcode for overlapping chunks
Potential bug fix: free sector always calculated.
It was not calculated for chunks with unknown error codes
Typo fixes, add more TODO.
Rename _bytes_to_sector to bytes_to_sector.
Helper function is now considered public.
Move InconceivedChunk from world to region.
More temporary notes (TODOs)
Add region_analysis.py example script