extract model building logic into ModelBuilder so we can use it on the class level, too.
extract model building logic into ModelBuilder so we can use it on the class level, too.

apotonick/trailblazer,baweaver/trailblazer,plribeiro3000/trailblazer,robjacoby/trailblazer,baweaver/trailblazer,timoschilling/trailblazer,joshuawatson/trailblazer