Updated incoming links code so that if the incoming links ranking factor is...

Updated incoming links code so that if the incoming links ranking factor is not set than indexingn of the number of links per node is not done during cron, this is done to save system resources by eliminating excess queries for a feature that is turned off.  Additionally a note in the ranking title is left in parenthesis letting the site admin know that changing the incoming links ranking factor means that re-indexing the site will be necessary.