In this commit:
 - Changed get_item in JMResultBase so that a vector of same length as time is returned, independent of variability. (#2712)
 - Introduced methods JMResultBase.final and JMResultBase.initial returning the final and initial value resp. of a specific variable in the result. Also modified tests and examples so that they use final and initial instead of raw vector accesses.(#2712)
 - Changed some simulation examples using JMU to use FMU instead. (#2553)
 - Added asserts in some examples that did not have any before. (#2732) 

Also, made sure that all examples are in one of the test modules.