Packages without installation components or classes

This has become less of a priority to our product team; as with some of the Mirantis dev team, they were not sold on the idea of a load of un-actionable advertising space, so this one can be reduced in priority for now.
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Request for another package type 'third_party-service' that doesn't have installation components, just information (name, author, logo etc) and links. The use case for this is to point people at services that are not yet integrated with Openstack but are of interest to them, as part of our larger goal to make murano a core part of our developer experience and provide one place for developers to go to find things that are useful to them.

The actual work involved in this is being able to list non-application types, but treat them differently (no 'deploy into environment') and potentially be able to filter on them. They fit into the same categorization structure that already exists.

Extension of information that can be supplied in packages will be a separate blueprint.

An extension of this will be managing credentials (as a separate later blueprint, probably relying on Barbican).

Docs:
https://etherpad.openstack.org/p/Murano3rdPartyServices