As part of CONNECTORS-781, create at least one multiprocess test, and debug multiprocess code.

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/trunk@1547167 13f79535-47bb-0310-9956-ffa450edef68
Create a rebased branch to work on CONNECTORS-781.

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/branches/CONNECTORS-781@1547170 13f79535-47bb-0310-9956-ffa450edef68