Follows and relationships (#27)

* Follows -- create and undo, both remote and local
* Statuses -- federate new posts, including media, attachments, CWs and image descriptions.

internal/api/security/security.go

@@ -43,5 +43,6 @@ func New(config *config.Config, log *logrus.Logger) api.ClientModule {
 func (m *Module) Route(s router.Router) error {
 	s.AttachMiddleware(m.FlocBlock)
 	s.AttachMiddleware(m.ExtraHeaders)
+	s.AttachMiddleware(m.UserAgentBlock)
 	return nil
 }