Add returns to end of functions (#422)

PhpStorm flags functions that don't have returns at the end so this PR rearranges code so that the returns are always at the end, or in one case adds one that was missing.

include/layout.inc

@@ -43,7 +43,8 @@ function highlight_php($code, $return = FALSE)
     ) . '</div>';
 
     if ($return) { return $highlighted; }
-    else { echo $highlighted; }
+    echo $highlighted;
+    return null;
 }
 
 // Same as highlight_php() but does not require '<?php' in $code
@@ -54,8 +55,8 @@ function highlight_php_trimmed($code, $return = false)
     $highlighted_code = preg_replace("/\&lt;\?php(\<br \/\>)+/", '', $highlighted_code, 1);
 
     if ($return) { return $highlighted_code; }
-
     echo $highlighted_code;
+    return null;
 }
 
 // Stats pages still need this
@@ -549,6 +550,7 @@ function get_news_changes()
         $title = $NEWS_ENTRIES[0]["title"];
         return "<a href='{$link}'>{$title}</a>";
     }
+    return false;
 }
 
 function news_toc($sections = null) {