update phpmd ruleset to use (subset) of cleancode

fix various minor issues reported by static analysis
remove redundant php closing tag from several more files

plugins/search_sphinx/init.php

@@ -61,5 +61,4 @@ class Search_Sphinx extends Plugin {
 	function api_version() {
 		return 2;
 	}
-}
-?>
+}

plugins/search_sphinx/sphinxapi.php

@@ -973,6 +973,10 @@ class SphinxClient
 		return pack ( "N", $t2 );
 	}
 
+	/**
+	 * @SuppressWarnings(unused)
+	 */
+
 	/// add query to multi-query batch
 	/// returns index into results array from RunQueries() call
 	function AddQuery ( $query, $index="*", $comment="" )