ASCE41 Max Direction Factors

Deal with max direction factors more elegantly in ASCE41 calculations for BSE-1E, BSE-2E, and Custom probabilities. Since these data are pulled from UHT curves which have different pre-applied (i.e. do not include) max direction factors, these needed to be treated differently here.

Current solution hard-codes appropriate max-direction factors into the code. Prefer a data-driven approach.