DJUTILS utilities for unit tests

Element	Missed Instructions	Cov.	Missed Branches	Cov.	Missed	Cxty	Missed	Lines	Missed	Methods	Missed	Classes
Total	45 of 423	89%	14 of 34	58%	13	40	6	93	1	23	0	3
org.djutils.test		89%		58%	13	40	6	93	1	23	0	3