* Remove Prefix Id and Plugin Name fields. Creating catalogs now require either the plugin id or the name of the plugin resource (but not both). Host Catalogs and Host Sets API resources now have a read only plugin field populated with plugin info. Host Catalogs have a plugin id field as a top level field.
* Create minimalistic plugin map and test plugin.
* Pass secrets and attributes to the plugin when creating catalogs or sets. Add tests for CreateSet and CreateCatalog repo methods.
* make fmt and extract out getPrivateCatalog and getCatalog helper methods.
* Exporting TestPluginServer so it can be used in the handlers.
* Keep separate persisted data from host catalogs lookups which facilitate passing it onto the plugins.
* Add TODO to merge get Catalog and get Persisted data.
* Adding tests for unimplemented being returned by the plugin.
* Use GetFields() instead of AsMap() to confirm attributes should be populated. Make clone consistent between catalog and sets.
Co-authored-by: Jeff Mitchell <jeffrey.mitchell@gmail.com>