pubsubhubbub: use atom rel=self link (when available) when subscribing
to push-enabled feeds
pubsubhubbub: disable feed url checking when subscribing for the time being, expand error messages a bit
quickAddFilter: if text is currently highlighted, use that instead of active article title for placeholder text
getFeedArticles(): Use valid query to get count of matching articles.
Merge pull request #326 from rwetzlmayr/fixes

getFeedArticles(): Use valid query to get count of matching articles.