LPS-34081 Refactoring of the Journal Portlet (and related) to the new staging

Hey Julio,

Dániel has finished working on the Journal refactoring, and here I'm sending it to you. We have review the changes with Dániel step by step, so I cannot really add more info, maybe that this was at least as difficult to implement as the DL :)

Tests are coming also, Dániel has already finished some of them, but it will need a check but the bottom line is: test are coming.

Thanks,

Máté