Add Starting and Ending KPI's (#7811)

* First draft of the solution

* Add missing changes

* Remove the new KPI's from report

* Fix bugs

* nit change

* Add improvements

* Fix regression tests

* Solve bugs in the regression algos

* Fix regression tests bugs

* Expand unit tests and add minor changes

Algorithm.CSharp/CustomDataMultiFileObjectStoreRegressionAlgorithm.cs

@@ -192,6 +192,8 @@ namespace QuantConnect.Algorithm.CSharp
             {"Compounding Annual Return", "0%"},
             {"Drawdown", "0%"},
             {"Expectancy", "0"},
+            {"Start Equity", "100000"},
+            {"End Equity", "100000"},
             {"Net Profit", "0%"},
             {"Sharpe Ratio", "0"},
             {"Sortino Ratio", "0"},