Better define the schema object namespaces

Right now tables/views, procedures, and functions are in separate namespaces. There are three downsides

• procedural to relational mapping effectively puts procedures and tables in the same namespace
• the default logic in the permission system does not check the resource type, so there is an assumption that the names won't conflict.
• creating a virtual function defined by teiid procedure language (which we should be more strict about) is represented in system metadata as a procedure, but is resolvable as a function of the same name

We either need to put everything in the same namespace, or be more exacting with the permission logic.