Custom filtering for resource types

[nturinski]

@aweininger We discussed having some more filtering groups for resource types since we're starting to accrue a pretty large variety of extensions contributing.

Couple ideas:

• Hide some by default unless they have a resource of that type
• Have different filtering types, such as "Core" which would be our extensions, "Supported" which would be resources with corresponding extensions, and "All" which is showing every resource
• Maybe supporting a "Custom" filter that lets users filter similar to how it works for subscription. Have to consider how this will affect resource groupings.