Fix "Could not delete" Exception on removeDirectory

Author: Flyingmana

src/MagentoHackathon/Composer/Magento/Deploystrategy/DeploystrategyAbstract.php

@@ -379,7 +379,7 @@ public static function rmdirRecursive($dir)
     {
         $fs = new \Composer\Util\Filesystem();
         if(is_dir($dir)){
-            $result = $fs->removeDirectory($dir);
+            $result = $fs->removeDirectory(rtrim($dir,'/'));
         }else{
             @unlink($dir);
         }