btrfs superblock fuzzer

Bitflips in sb items, recalculate checksum, try to mount.

Signed-off-by: David Sterba <dsterba@suse.cz>
test-fsmark-16p: update help

Signed-off-by: David Sterba <dsterba@suse.cz>
creat_unlink: minor update

Signed-off-by: David Sterba <dsterba@suse.cz>
lib/w-fi-df: clean and update help

Signed-off-by: David Sterba <dsterba@suse.cz>
New test: git commit snapshots

Signed-off-by: David Sterba <dsterba@suse.cz>
lib: incoming: bunch of utilities or test stubs

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: git-based stress lodad generators

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: subvolume stresstests

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: transaction load for crash tests

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: many loop devices test

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: csum bug from 3.8 reproducer

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: inode-corr.py

Signed-off-by: David Sterba <dsterba@suse.cz>
lib: scsi host from dev

Signed-off-by: David Sterba <dsterba@suse.cz>
incoming: mass file creator

Signed-off-by: David Sterba <dsterba@suse.cz>
test: subvol stress

Signed-off-by: David Sterba <dsterba@suse.cz>