Create a model which represents all top-level items and, potentially, one
expanded trip as a flat list.
Pass down roles to the source model and let the source model handle that. We'll
have to do some ifdef-ery, but so be it.
Additionally, compile the base model on mobile as well.
This contains a couple of hacks to make things compile at all.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
