CAS-1257: Allow support for custom attribute filters when validating a service

By factoring out the attribute filtering process out of CASImpl, support could be made available via custom injection of filters that would do more other than making sure a registered service received the right set of allowed attributes. 

This commit places the mapping of filters and services inside the services management tool, and provide a regex attr filter. the default attr filter behavior is preserved, but placed into a new default attr filter.