Code to define modeltype RM-2380

create a modeltype table used by models and pfts. The table is
initialized with the types already in the models (not pfts). All models
and pfts are associated with a modeltype next.
User can add/edit modeltypes and see the pfts/models associated with it.
Since you are searching on the model type name in a different table now, you need "modeltype" in your SEARCH_INCLUDES list.  Otherwise, PFT searches is totally broken. (It's also needed for sorting on modeltype name as it was in the models table.)