Create a REST enpoint to publish document

We want to create a REST endpoint/operation in order to publish document, rendition or even tree snapshot.

Seen during development of publication feature through REST for 10.10.
We miss a dedicated REST endpoint to correctly publish documents.
This endpoint should leverage PublisherService which allow different publication way by contributions. This is how publication with rendition and/or publication with validation work.

As a note: CoreSession#publishDocument doesn't fire documentPublished event because a document can be published and waiting for validation. This is PublisherService which decides which events to fire. For instance documentPublished or documentWaitingPublication.

Operations such as PublishDocument or PublishRendition should be reviewed because they don't leverage the service.