Project autoplot-test051

run scripts found in scripts/test051, check that results haven't changed.  The tests that start with [a-z] are run.  The goal here is to provide an easy method to create tests, where users of the software can create arbitrary tests, and ultimately a method where people can submit tests for nightly testing.  Artifacts starting with "test" and ending with ".txt" and ".png" are archived.

Eventually, scripts with the parameter "test" will run through all enumerated test numbers, besides zero (which can mean normal operation).