Folders

This PR brings in further integration for OAE in the following aspects:
 - Activities
 - Search
 - Previews
 - REST Docs
 - Extra functionality such as updating, deleting, ..
Might be able to do something similar to the content API:

```
Get a full content item profile. Next to the basic content profile, this will include the created date, the profile of 
the user who originally created the content, and a isManager property specifying whether or not the current user can
manage the content.
```