Legacy body parsers trait. Basically all this does is define a "parse" member with a PlayBodyParsers instance
constructed from the running app's settings. If no app is running, we create parsers using default settings and an
internally-created materializer. This is done to support legacy behavior. Instead of using this trait, we suggest
injecting an instance of PlayBodyParsers (either directly or through BaseController or one of its subclasses).
(Since version 2.6.0) Inject PlayBodyParsers or use AbstractController instead