Refactor manotypes:vnf-configuration

1) Rename manotypes:vnf-configuration to manotypes:vca-configuration
2) Add manotypes:vca-configuration to the VDU to support multi-VDU scenarios
3) Add support for relations to the juju container

Signed-off-by: Adam Israel <adam.israel@canonical.com>
Change-Id: I3ac6d483284dcf68141d5031ce94e8b915d35107