small optimization in the ':not' pseudo-class resolver by avoiding an unneeded assignment, added fall back parameter for the 'compileGroup()' calls used in both 'match()' and 'select()' methods.
small optimization in the ':not' pseudo-class resolver by avoiding an unneeded assignment, added fall back parameter for the 'compileGroup()' calls used in both 'match()' and 'select()' methods.

dperini/nwmatcher,dperini/nwmatcher,dperini/nwmatcher