* Add UserNote model
* Add UI for user notes
* Put comment in relationships entity
* Add API to create user notes
* Copy user notes to new account when receiving a Move activity
* Address some of the review remarks
* Replace modal by inline edition
* Please CodeClimate
* Button design changes
* Change design again
* Cancel note edition when pressing Escape
* Fixes
* Tweak design again
* Move “Add note” item, and allow users to add notes to themselves
* Rename UserNote into AccountNote, rename “comment” Relationship attribute to “note”
