Merge branch 'release-1.4'
Merge branch 'master' of github.com:mfriedel/pydpiper into develop
* added re-trying / re-submitting of stages twice before considering the stage are truly failed. On occasion, stages fail where the error message is along the lines of: "file something.xfm does not exist". However, the file does exist. It is create just prior to attempting the stage that fails. This could be due to an nfs race condition. I've ran a number of tests with this stage re-trying option, and the error that seemingly is caused by the nfs race condition is solved by this. Those stages are only resubmitted once, at which point the stage runs fine. For stages that truly fail, the error message will appear after the stage is resubmitted twice. So that behavior is still correct.