Added flask.copy_current_request_context which simplies working with greenlets

flask/app.py

@@ -1821,3 +1821,9 @@ class Flask(_PackageBoundObject):
     def __call__(self, environ, start_response):
         """Shortcut for :attr:`wsgi_app`."""
         return self.wsgi_app(environ, start_response)
+
+    def __repr__(self):
+        return '<%s %r>' % (
+            self.__class__.__name__,
+            self.name,
+        )