Add flags to disable Novelty in Appraiser

[MarkDWilliams]

1. Add a new field similar to pk which we pass in our call to Appraiser
2. Set the weight for novelty to 0 in scoring.py

[MarkDWilliams]

UPDATE: Skipping step 1. Max says he's going to just comment out the novelty call rather than implementing a flag as there are no plans to support the toggling of novelty calculations on an ongoing basis, just temporarily for the purposes of testing. Will still need to do 2