e2fsprogs: add supported file attributes to ext4.5 manpage

The chattr(1) manpage now refers users to filesystem-specific
manpages for details on supported attributes, so add those to
ext4.5.

I've left out oddities like being able to set the compressed
or no-tail-packing flags, or setting data journaling on ext2.

That behavior seems like a bug, not a feature.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
e2fsck: fix spelling error (strage vs storage)

Reported-by: Philipp Thomas <pth@suse.de>

Signed-off-by: Theodore Ts'o <tytso@mit.edu>