delete fits output files
add basic logging of element changes by comparing DBObject ("Document")
of modified Elements.
no more need for merging rule - check Single Value status over all
possible conflicts
collect log entries during rule execution and output them at once when
done - to easy debugging!
Rules: clean up logging and remove unnecessary imports
Rules: now supports multiple files
Rules: split up into several files
Element: allow merging list of metadatarecords
	new addLog method
LogEntry: add new ChangeType (ADDED)
move cache lookup to metadatautility (no longer static)
drools code cleaups
enhanced (though dirty) logging