fix nav links for non-index.html pages
fix nav links for non-index.html pages

makinacorpus/StoryMapJS,BenHeubl/StoryMapJS,jorol/StoryMapJS,jorol/StoryMapJS,1modm/StoryMapJS,BenHeubl/StoryMapJS,1modm/StoryMapJS,cr3ative/StoryMapJS,BenHeubl/StoryMapJS,miguelpaz/StoryMapJS,makinacorpus/StoryMapJS,cr3ative/StoryMapJS,miguelpaz/StoryMapJS,1modm/StoryMapJS,1modm/StoryMapJS,makinacorpus/StoryMapJS,wangjun/StoryMapJS,jorol/StoryMapJS,miguelpaz/StoryMapJS,cr3ative/StoryMapJS,cr3ative/StoryMapJS,wangjun/StoryMapJS,BenHeubl/StoryMapJS,wangjun/StoryMapJS,wangjun/StoryMapJS,jorol/StoryMapJS