Add ability to save user search queries

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Possible features:

• User can save and name search queries
• Users can share search queries
• Search queries are only accessible by users who have been given access
• Users can edit saved searches
• Users can generate SDK and API requests for a saved search (since the request body for these endpoints would be the saved search itself, possibly not necessary, clients can provide this tool)

Implementation notes:

• New mongo collection, could possibly inherit from ContainerStorage class
• Endpoints would be GET (by id and all (that user has access to), POST (new and @id for replace) and DELETE by id
• Use existing permissions list and endpoints to handle access. Mappings to admin, ro etc to be determined