Do not test selenium in Travis
Do not test selenium in Travis

It fails sporadically and causes timeouts.
cga-harvard/hypermap,cga-harvard/hypermap,cga-harvard/hypermap,cga-harvard/HHypermap,cga-harvard/HHypermap,cga-harvard/HHypermap,cga-harvard/hypermap,cga-harvard/HHypermap