Fix closure output so that it only applies to that run

I mistakenly hacked in the functionality using the current displayStdout functionality
which was incorrect. Needs to only use that function on the output of the current
command, and not set it across the board.

src/MrRio/ShellWrap.php

@@ -54,14 +54,15 @@ private static function __run($arguments)
     {
         // Unwind the args, figure out which ones were passed in as an array
         self::$stdin = null;
+        $closureOut = false;
 
         foreach ($arguments as $arg_key => $argument) {
             // If it's being passed in as an object, then pipe into stdin
             if (is_object($argument)) {
 
                 // If it's a anonymous function, then push stdout into it
                 if (get_class($argument) == 'Closure') {
-                    self::$displayStdout = $argument;
+                    $closureOut = $argument;
                     unset($arguments[$arg_key]);
                 } else {
                     self::$stdin = strval($argument);
@@ -155,6 +156,9 @@ private static function __run($arguments)
                     $outputFunction($stdout);
                 }
 
+                if (is_callable($closureOut)) {
+                    $closureOut($stdout);
+                }
                 $output .= $stdout;
             }