Compares to a LociMap-class objects to determine if
the first one is a superset of the second. If it is, the function returns NULL.
If it is not, the function return a LociMap-class object that is
a superset of both a LociMap-class objects.
findQtlIndex(activeQtl, traitQtl)an integer vector for relative positions of traitQtl on activeQtl
a LociMap-class representing all active QTL
a LociMap-class representing QTL for a trait of
interest