Still more DynamicParam fixes

To retrieve the dynamic parameters for a function, the code now executes a script block which is bound to the scope of the same module as the mocked function's original location.  This allows the dynamic parameters to be fetched successfully even when they reference script-scoped variables, and the caller is in a different module scope.
Merge pull request #207 from dlwyatt/DynamicParamFix

Still more DynamicParam fixes