In general, there's no reason to use by-ref on objects unless
the hook is supposed to replace them (this one isn't).
Change-Id: I153a7d590faceb1e2c4fe7d95a5cb931cda0c301
'SpecialSearchResults': Called before search result display
$term: string of search term
-&$titleMatches: empty or SearchResultSet object
-&$textMatches: empty or SearchResultSet object
+$titleMatches: empty or SearchResultSet object
+$textMatches: empty or SearchResultSet object
'SpecialSearchResultsPrepend': Called immediately before returning HTML
on the search results page. Useful for including an external search