Add og:site_name to embed template
Add og:site_name to embed template

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