[PLAT-2941] Added an extra property to indicate which technique was used to get the prices
Moved the Black calculation method property name into a separate class
[PLAT-2941] Added model type property for equity index option functions
[PLAT-2941] Adding a model type property for commodity future option functions
[PLAT-2942] BAW and Bjersund-Stensland functions for commodity future options now only work for American expiry options