* Delay security removal when there are pending settlements
* Add unit test
* Minor fixes
* Minor fix
* Replace HasUnsettledFunds method with UnsettledCash in ISettlementModel
* Minor fix
* Minor fix
* Address peer review
Replace ISettlementModel UnsettledCash property with GetUnsettledCash method that returns a CashAmount instead of a decimal to include the currency
* Minor fix
* Address peer review
* Improve GetFillModel()
* Add support for other methods
* Add regresion algos and improvements
* Make Python algorithms regression tests
* Improve unit tests
* Minor changes