Integrate with office hours module

[acrollet]

Office hours has a 8.x-1.0 release, let's integrate with it. If a content type is enabled for hourly bookings, let's show a checkbox in the BEE tab when editing the node:

"Set Open Hours"

If it is checked, let's show the UI and allow office hours to be set. They should be shown on the back-end calendar the way we do with Spaces.