Cleanly record failed docking results.

[hmacdope]

I guess a problem to solve in the future is how to cleanly record failed results. Right now you would just grep the log files, which is ok but not great. I could see an argument for a POSITDockingResult object that can handle failed results but that seems annoying to implement. We could mimic what @jthorton did in the pose generation code with a POSITDockingResults object instead of a list with failed and posed properties that are each lists of, i.e. POSITDockingResult and POSITDockingResultFailed or something (maybe the DockingInputBase).

Originally posted by @apayne97 in #1018 (comment)