Phriction - move "move" to modern editor + transactions

Summary:
Ref T4029. Much like D10756, D10761 this does the bare minimum to get things in there. I have a sticky with "TODOs" about moving the error-checking business logic into the editor in all three cases.

Up next - policy...

Test Plan: moved a document and it worked! verified no feed story. verified both documents involved looked good

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T4029

Differential Revision: https://secure.phabricator.com/D10763