Introduce new DI container

- Adding Friendica\DI class for getting dynamic classes
- Replacing BaseObject::getApp() with this class

src/Module/Debug/Feed.php

@@ -5,6 +5,7 @@ namespace Friendica\Module\Debug;
 use Friendica\BaseModule;
 use Friendica\Core\L10n;
 use Friendica\Core\Renderer;
+use Friendica\DI;
 use Friendica\Model;
 use Friendica\Protocol;
 use Friendica\Util\Network;
@@ -18,7 +19,7 @@ class Feed extends BaseModule
 	{
 		if (!local_user()) {
 			info(L10n::t('You must be logged in to use this module'));
-			self::getApp()->internalRedirect();
+			DI::app()->internalRedirect();
 		}
 	}