Add refrigerant charge factor for heating and apply to COP

[nealkruis]

Per new changes in ACM, we need to add a separate charge factor for heating. In the performance map model, charge factors are applied to the capacity, but we (Abram and I) think they should really be applied to the COP to avoid interactions with autosizing.

[chipbarnaby]

As agreed, the changes were implemented by modifying gross COP or gross input power. This is a change from the prior implementation that modified capacity.

The formulation shown above modifies the net COP. I don't think the CASE team has any grasp of the fan power issues. I made the radical assumption that charge does not effect fan power.

[nealkruis]

Complete in #536.