1. add barbican related policy
2. add barbican into service_mapping
3. add releatenote for barbican
4. update releatenote for zun and magnum
Change-Id: I366e4482617654baab9091736e6f2b186aed6371
1. add magnum install into post_install.sh
2. add magnum into SUPPORTED_SERVICE_EPS and PREFIX_MAPPINGS
3. add magnum policy
Change-Id: I10d2d337331d8c4857f6e58331e545eead0bf26f