return logic tidied up for command interpretation

lib/commandinterpreter.php

@@ -298,8 +298,6 @@ class CommandInterpreter
                     $result = new TrackingCommand($user);
                 }
                 break;
-            default:
-                $result = false;
             }
 
             Event::handle('EndInterpretCommand', array($cmd, $arg, $user, &$result));

lib/implugin.php

@@ -402,9 +402,8 @@ abstract class ImPlugin extends Plugin
             $chan = new IMChannel($this);
             $cmd->execute($chan);
             return true;
-        } else {
-            return false;
         }
+        return false;
     }
 
     /**