Removed the dual properties file, and now we have all the properties mer...

...ged into usergrid-default.properties. Updated the core persistence setup to reflect the change.
This property should be removed, it is redundant and duplicates what is in the new cassandra.hosts and cassandra.port properties. 

Once you remove this property, code in Usergrid will break (probably in CassandraService and CassandraResource). That code needs to be rewritten to use the new properties in stead.