Tolerate a null defaultPath and use it as the special case of general command line

 This is as opposed to zero-length string, which can happen by accident when a user enters nothing as the path to an executable. Why anybody would think that's a good idea I really don't know, but since there is no easy way to change it (since that menu entry gets removed) it shouldn't be detected.
Add "LongRunning" annotation and use it as a category for tests, skip test methods annotated with "LongRunning" unless property is set