Adding DSEvaluation's Assert function over to RecordedTest
1. Implemented "OpenFileCommand" recordable command.
2. Factored "DynamoModel.Open" method into "OpenInternal".
Implemented "RunCancelCommand" recordable command
Updated both "Run" and "Cancel" buttons to use "RunCancelCommand"
Added TestRunCancelCommand and TestCreateNodesAndRunExpression test cases

Conflicts:
	src/DynamoCore/Core/DynamoController.cs
Added recordable test case for simple CBN node to code using DSEvaluation mirror.
Fix the protection level of helper method
Merge pull request #913 from l2obin/RecordedTestWithMirror

Adding DSEvaluation to RecordedTest.