Simplify the handling of exceptions thrown during custom test case parameter generation now that each Case has-a CaseExecution of its own.
Simplify the handling of exceptions thrown during custom test case parameter generation now that each Case has-a CaseExecution of its own.

EliotJones/fixie,KevM/fixie,fixie/fixie,bardoloi/fixie,JakeGinnivan/fixie,bardoloi/fixie,Duohong/fixie