Put model statically in class. Prevents saving/loading issues.
Adapter classes now inherit from Model classes. Linking has changed, solving non-DAG problems.

Add basic ViewProviders. Use claimChildren to order the tree. Currently broken since using obj.InList doesn't seem to work.

Regrouped and renamed Adapter classes.

Regrouped and renamed Model classes.

Introduced methods for reverse lists.
Merge pull request #45 from FRidh/master

Adapter classes now inherit from Model classes