AAI-2184 Robot testcases for BBS use case Dublin

Update .gitignore for pydevproject file
Update Robot testcases for CCVPN use case Casablanca
Add assets and resources for BBS use case Dublin
Add regression testsuite for Dublin
Add subobject handling
Add service-subscription sub-object
Add service-instance sub-object
Add metadatum sub-object
Re-factor top-level classes as subobjects of network and business namespaces
Updated filenames with csit prefix
Needs the robot/library/ sub-directory of testsuite repo

Change-Id: I9956da0b3a6c0bdf782ad486ea4680bc5460c406
Issue-ID: AAI-2184
Signed-off-by: Keong Lim <keong.lim@huawei.com>