text: Title: Resolver for MongoengineConnectionField - Add Authorization Token
  Body: Hi 
  
  I have been using graphene-mongo for a while now. I use all resolvers and mutations post validation of an Access token in the HTTP `Authorization` header. However, I am not aware of how I can do that for a `MongoengineCollectionField`
  
  For example, I have defined it as follows
  ```python
  class Query(graphene.ObjectType):
      all_projects_to_models = MongoengineConnectionField(Project)
  ```
  
  and it works functionally as expected
  
  My question is, what does this object return? and is there a way I can write a resolver for this with the Authorization validation done before allowing access