Bug 536280 (RHQ-647)

the mbeanserver can provide us with metadata about the structure of the actual mbeans in some jmx-enabled server.  we need to come up with a way to specify plugin metadata that will know how to read and parse this mbean metadata in a generic way so as to automatically create resource types.  once we have the types created on the fly, we shoudl be able to requery the mbeanserver and impot all mbeans into the inventory as resources of their appropriate, dynamically-created type.

note: this will not alter any metadata that has been hard-coded into plugins that talk to jmx-based resources, this merely augments it.  as a result, there is a natural expectation for some resources to be logical duplicates of one another - this is ok.