Namespace filter: basic functionality
Initial, client-side only implementation of namespace filter.
All results in all namespaces are always fetched from the server. The displayed results are filtered in on the client using a new "filteredResults" computed property which checks the namespace of each result against the selected namespace values.
A "reset namespaces" button has been added to the namespace filter dialog as well.
Future work:
- Add NS selection to the URL as a query parameter
- (optional) - change the request made to the API back-end so that we don't retreive all results in all namespaces by default