Add "favourites" to props and rooms Merged

A client request I've received is that it would be nice if they can add favourites to our rooms and props. I think rooms can kind of be handled by making them into templates but it does seem like it is lacking from the props.

If clients want to use our props but need to be "On Brand" it is pretty difficult right now to sort through all our +1000 props and would be nice to have selected e.g. the 300 different props you think are relevant for you as a client. - Product: Studio - Source: Sofacompany - Submitter: Rolf Bender