- Remove unrequired `GetBuyingPower`
- Making `BuyingPowerModel.GetMaintenanceMarginRequirement` protected
instead of public
- Adding `GetMaximumOrderQuantityForDeltaBuyingPower` to replace
public `GetMaintenanceMarginRequirement` and improve API experience for
consumers like the `DefaultMarginCallModel`
- Adding new unit tests
- Adding _some_ of the missing PyObject.Dispose calls. In the cases
where C# is calling the Python side.
- Note that Python calls to C# code is correctly handling the
disposure of resources.
- Adds `MarginCallModelPythonWrapper` to wrap a python class that represents a margin call model.
- Adds `SetMarginCallModel` to enable the setting of custom margin call model.
Jhonathan Abreu