The initial version of libbtrfsutil did not follow a unified naming
scheme that's usually used for libraries like those provide by
util-linux. Add aliases that are "btrfs_util_" + object + action +
suffix.
The library version changes to 1.3 but there's no new functionality,
only the aliases added. New functions can be added in the future without
possible confusion when the same action could apply to different
objects.
Issue: #574
Signed-off-by: David Sterba <dsterba@suse.com>
