Determine access strategy for SYS/pg_catalog

The SYS and pg_catalog schema mainly exist for metadata reporting. It would probably be good to make the always be accessable.

The only issue is what the access policy should be for the system procedures:

GETCHARACTERVDBRESOURCE
GETBINARYVDBRESOURCE
GETVDBRESOURCEPATHS

GETXMLSCHEMAS

refreshMatVeiw
refreshMatVeiwRow

The first three are probably no longer useful as general procedures. I'm not familiar with any customer usage. Unless someone adds custom files to a VDB, the only thing that could be retrieved are the visible model xmis and schemas.

The fourth procedure is really just a helper method to get at schemas associated with a particular document model. These resources would already be accessible via getXXXVDBResource. Again I'm not aware of customer usage for this procedure.

Since they are read-only and restricted to only visible entries we could just as easily always allow access to the GET procedures, or we could just as easily remove them all since they aren't particularly useful.

That leaves us with the refresh procedures. Theses do perform update actions and should be restricted. One possibility is to restrict their usage based upon the permissions of the target view. The other option is to move them into a sub schema e.g. SYS.admin.refreshMatView that would be subject to access restrictions, and can be more easily targeted by explicit roles. If we went the role route, then the tooling could have a button to "create admin role" that would create a role named admin with all permissions including permissions against SYS.admin.