tests: create crcsum progam to support resizing tests

The only checksum program which we can reliably count upon being
installed on all systems is "sum", which is not a particular robust
checksum.  The problem with using md5sum or sha1sum is it hat it may
not be installed on all systems.  So create a crcsum program which is
used so we can validate that a data file on a resized file system has
not been corrupted.

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