Add a method to register multiple blueprints.

flask/app.py

@@ -931,6 +931,10 @@ class Flask(_PackageBoundObject):
             first_registration = True
         blueprint.register(self, options, first_registration)
 
+    def register_blueprints(self, blueprints):
+        for blueprint in blueprints:
+            self.register_blueprint(blueprint)
+
     def iter_blueprints(self):
         """Iterates over all blueprints by the order they were registered.