Added an Action Inspection Property.
Invoked action upon Execute.

Returning null is incorrect, so future tests should guard against that.
Returned PassedResult after successful invocation

of test action.
Renamed Action to TestAction,

in order to be a bit more explicit about the role played by this delegate.
Passed correct method instance to PassedResult.
Passed correct method info to base constructor.
Refactored Execute method to use protected

test method value.
Added a null Guard Clause to FirstClassCommand's

constructor.
Passed correct timeout value to base constructor.
Made sure that DisplayName has a proper value.