Rename CONNECTORS-856-2 branch to CONNECTORS-856

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/branches/CONNECTORS-856@1558367 13f79535-47bb-0310-9956-ffa450edef68
Pull up changes for CONNECTORS-856.

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/branches/CONNECTORS-856-2@1567650 13f79535-47bb-0310-9956-ffa450edef68