tune2fs: replace the -r option with -E revision=<fs-rev>

tune2fs: replace the -r option with -E revision=<fs-rev>

Revision 0 file systems are needed for compatibility with pre-1995
Linux kernels (older that version 1.2).  Other for testing and
computer science archoelogy, there are no valid reasons for using this
feature.  Revision 0 file systms do not support any file system
extensions beyond what was present in Linux 1.0 kernels, and only
support 128 byte inode sizes, which means that the file system will
only support file dates after the Unix epoch in 2038.

Users who use -r 0 are almost certainly doing so by mistake (for
example, perhaps they meant -m 0 but they typed -r 0 instead).  As a
result they get a very badly cripped file system that won't support
SELinux, post-2038 dates, on-line resizing, etc.  So remove the -r
option and replace it with the extended option "revision", to prevent
users from falling into this trap.

Addresses-Debian-Bug: #1086603
Signed-off-by: Theodore Ts'o <tytso@mit.edu>