Publication: Create preview step for publication

Currently, in the publication process there's a first step of setting the publication parameters and a second step for the actual publication. An intermediate step should be provided as a preview step.

It should:

• display the published book reference,
• display a list of used libraries and their versions, with a link to the libraries' management UI,
  • status of the libraries (published or not).
  • if not published, a link to the library publication should be provided
• display a list of all the pages that are going to be published, based on the publication parameter, and their status
• depending on the selected behaviour (see BVERSION-83), if "Cancel" is selected, it might be good to display a message to the user (explaining that the target is already populated) and prevent him from running the job