QPID-5064: Install Dispatch Python modules.

Added a needed check for the Python interpreter so that the Cmake
environment can then interrogate Python for the proper library path.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1517023 13f79535-47bb-0310-9956-ffa450edef68
QPID-5096: Install the qpid-dispatch.conf file.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1517029 13f79535-47bb-0310-9956-ffa450edef68