Fixed bug and extended unit test for GalaxyWorkflowEngine
- GalaxyWorkflowEngine: only check whether an output file can be downloaded in the checkWorkflowResults method when automatic download is on.
- GalaxyWorkflowEngineTest: extended the runWorkflowTest method with the historyReady parameter to simulate timeouts, and with the outputIdCount parameter to vary the number of outputs (and added the getWorkflowOutputIds method).