fixed lookup source key
added sample_type filters
expanded sample_types lookup definition
refactored to include all elements from lookup
refactored sample_type logic into model
removed unneeded webapp objects
updating configuration specs
overriding fetch to ensure success is called
refactoring datamodel loading logic
deferred model loading; cleanup
fixed logging
refactored dataloading (again) to simplify logic, and allow for dynamic loading of backbone models