Only recent authors can publish a collab doc

Only users who recently editted a collaborative document can publish it.
This should avoid situations where a user who is only viewing a document
triggers a publication under his name even if he did not make any
changes himself.
Fixed up failing unit tests for publishing collaborative documents
Merged master into simong/collabdocs-recent-authors
Merged master into simong/collabdocs-recent-authors
Merge oaeproject/master into collabdocs-recent-authors
Add which etherpad server is failing in error logs
Merged master into simong/collabdocs-recent-authors
Publishing collaborative documents happens by responding to MQ messages

We’re no longer publishing collab docs through the REST api. Etherpad
will send OAE a message (via RabbitMQ) whenever a user leaves the pad
and made any edits.
Fix for failing collaborative doc preview test
Code / jsdoc cleanup
Emitting an `editedCollabdoc` event when a user editted a collaborative
document that did not generate in a new revision. This also triggers an
activity for that user and pad.
Asserting only 1 revision gets created
Merge branch 'collabdocs-recent-authors' of https://github.com/simong/Hilary into collabdocs-recent-authors
Minor documentation follow-up