Sometimes when testing a filter the database becomes unresponsive, stuck
in a long query.
Solution: properly join ttrss_entries and ttrss_user_entries instead of
working with their carthesian product.
Runs HTML and enclosures array through a plugin hook when rendering an article's enclosures in format_article_enclosures(). Allows plugins to override handling of how enclosures are presented by either filtering the array of enclosures, or generating the HTML to add to the article content.
Currently, TinyTinyRSS can use raw SQL or the Sphinx search engine
for searching. It would be nice if other search engines (such as
Xapian) could be used, or if features of the underlying SQL engine
(such as MySQL's FULLTEXT indexes) could be leveraged. This commit
makes searching into a plugin hook, falling back to the builtin behavior
if no search plugin is active. The Sphinx search behavior has been
broken out into a plugin.
