Merge pull request #18 from ptcong/patch-1

remove duplicated config key

Author: taylorotwell

src/Application.php

@@ -1519,7 +1519,6 @@ protected function registerContainerAliases()
         'Illuminate\Contracts\Cache\Repository' => 'registerCacheBindings',
         'config' => 'registerConfigBindings',
         'composer' => 'registerComposerBindings',
-        'config' => 'registerConfigBindings',
         'cookie' => 'registerCookieBindings',
         'Illuminate\Contracts\Cookie\Factory' => 'registerCookieBindings',
         'Illuminate\Contracts\Cookie\QueueingFactory' => 'registerCookieBindings',