Feature Request - User commenting on objects

[patricklindsay]

Users should be able to comment on objects for example if a user wants to add an important note to a user or add some recommendations to a post someone has recently published.

They should be able to add these comments on the object show page (https://github.com/yamasolutions/integral/issues/19)

We'll need to come up with a design for this widget which will display previous comments as well as provide a form to create a new comment.