Update LIFO implementation used by rbh-find.

Under certain circumstances, 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.