Dump the previous changelog entries on error.

Add a debug function to dump the nth previous changelog entries that
are to be processed by the pipeline. Suppressed changelogs cannot be
displayed, since they are already gone.
Update LIFO implementation used by rbh-find.

Under certain circumtances, the array used could grow many times,
leading to a buffer overrun and heap corruption.
New rbh-find output to display stat info.

Added the -lsstat command line option. Each file is output like:
 [file,31532,12790,23,1365022640,1365022640,1365022640]=/mnt/lustre/foo

Format is [type, uid, gid, size, ctime, mtime, atime]=file name
New rbh-find output to list every file's OSTs.

Added -lsost.
(WIP) Store uid and gid in the database, instead of names.

That replaces the owner and gr_name attributes with uid and gid.

rbh-find now understands uid and group when passed as --user and --group.

TODO: request with wildcards in username or group names are not
supported.
(WIP) Scan a Lustre tree of any depth.

The scanning is now done from /mount_point/.lustre/fid/ instead of the
regular Linux path.

Note: using this patch creates a problem with the matching engine,
when the criteria is a name, for instance with the Ignore option of
FS_Scan.
Remove last dependancy on mysql.

Oracle's package is called MySQL, and we can't easily look for it,
because the system could be rpm/deb/... based. And rbh-config already
tests for the presence of the right binaries.