Fix issues in OSG_autoconf and gfdiff
CMS, Factory Ops
Edita (CMS Cat-A) and I used these tools in production and found a typo in one of the attributes in OSG_autoconf.
We also found out that if an entry passed to gfdiff is not existing in the xml, then the commands seems to hang indefinitely due to a "runaway regular expressions". I fixed it by making sure the entry exist before matching the regexp.