* New args to cbd format.
* HAVE_* -> COMPRESS_HAVE_*.
* Verify header params algorithm and compression.
* Move percpu alloc to lbdcache.
* Alloc percpu data in lbdcache_ctr, free in lbdcache_dtr.
* Fix command line handling.
* Move option/parameter validation to libcbd.
* Make resize argument the logical size.
* Make blkdev_pblk_* take dm_compress instead of block_device.
* Reinstate dm_compress.io_failed.
* Other misc stuff.