Update persistence-in-nservicebus.md
Update persistence-in-nservicebus.md

Changed to link both the 3.x and 4.x versions of NHibernate persistence.  I will also add a link to the 3.x doc to point at the 4.x doc.
pashute/docs.particular.net,WojcikMike/docs.particular.net,SzymonPobiega/docs.particular.net,pedroreys/docs.particular.net,eclaus/docs.particular.net,yuxuac/docs.particular.net