Macro for checking if a form param has a certain value or not.

       process ( paramName, paramValue, ifTrue, ifFalse  )

       paramName

       The name of the form param to pull from the session object.

       paramValue

       The value of the form param to check for

       ifTrue

       What to return if the value form param matches

       ifFalse

       What to return if the value of the form param does not match