Work on loading region files.
Fix decoding of tribytes. (big-endian three-byte values)
Improve the chunk data class.
Display loaded region files.
Add NSCoding to the chunk data class.
Add action validation for McChunks.
Fix drag & drop row removal if its a local drag.
(Row indexes are not reliable when items get expanded during a drag.)
Fix draging items into themselves if its a local copy drag.
Rename some variables that where improperly named.
Prevent dragging items that are not NBTContainers.
Fix rightclick menu disabled state for items which are not
NBTContainers.
Update .mca data in main thread.
Customize save panel.
(Only show allowed file types in the type popup. Show a `Compress Data`
checkbox for .dat and .schematic files)
Change file type names to something more descriptive.
Fix spacing of the save panel accessory view.