Allows attaching educations (via life events) to the character

Allow adding educations to characters. 

Adding an education is done via `POST  `/characters/:character_id/life_events/education/:education_id`

It's also possible to delete a life event from a character via `DELETE /characters/:character_id/:life_event_id`

In both cases, if the request is successful it will return to the character's edit form.