Subscribe to saved search feature

[ahamelers]

Once users can save searches, they should also be able to subscribe to see new datasets published that meet their search criteria. It should be possible to create an RSS feed for search results, and then create email updates from the RSS feed

• Create an RSS feed for SOLR search results (https://solr.apache.org/guide/solr/latest/query-guide/response-writers.html#xslt-response-writer)
• Check out options to send an email when new items are added to the RSS feed
• Allow users who have saved a search to subscribe to the RSS feed or email updates