Changes:
- btrfstune: incomplete fix to uuid change
- check: support repair of fs with free-space-tree feature
- completion: complete block devices and now regular files too
- core: port delayed ref infrastructure from kernel
- core: support write to free space tree
- docs: ship uncompressed manual pages
- dump-tree: new options for BFS and DFS enumeration of b-trees
- quota: rescan is now done automatically after 'assign'
- subvol: fix 255 char limit checks