match original markdown behavior for headings
match original markdown behavior for headings

whitefoxx/marked,googlearchive/marked,zodiac-xl/marked,zhenghuadai/marked,drmuey/marked,caiyongmin/marked,hujianfei1989/marked,readmeio/marked,chickencoder/marked,ulrikaugustsson/mdast,zhangxx/marked,Weasyl/marked,cadorn/marked,axter/marked,meihuabo/marked,sahat/marked,RemiArnaud/marked,slang800/marked,sooboy/marked,zhangxx/marked,googlearchive/marked,mrzie/marked,hujianfei1989/marked,kitsonk/marked,drmuey/marked,lazarofl/marked,dtinth/marked,whitefoxx/marked,reliefweb/marked,aroneiermann/marked,kwangkim/marked-react,mbranch/marked,ShareMyWorld/marked,Jucyio/marked,phiggins42/marked,bantic/marked,wangyue-ramy/marked,bobby-brennan/marked,martindale/kramed,amobiz/marked,gingkoapp/marked,FredrikAppelros/marked,mbranch/marked,axter/marked,weo-edu/marked,guypursey/marked,modulexcite/marked,npmcomponent/chjj-marked,martindale/kramed,takezoe/marked,thejameskyle/marked,grant-g/marked,yukkurisinai/mdast,weo-edu/marked,gdbooks/kramed,svacha/marked,Feder1co5oave/marktex,tranquangchau/marked,joaomilho/marked,dbkaplun/marked,gitterHQ/marked,kumu/marked,sahat/marked,qiweiyu/marked,LinuxBasic/react-marked,huiop368/marked,tranquangchau/marked,gitterHQ/marked,spicyj/marked-react,InnovaCo/marked,guypursey/marked,chcokr/mdast,webfby/marked,gjtorikian/namp,gdbooks/kramed,emilbayes/kramed,svacha/marked,emilbayes/kramed,wangyue-ramy/marked,takezoe/marked,helphi/marked,shovon/marked,udacity/marked,Guichaguri/marked,FredrikAppelros/marked,amobiz/marked,hgGeorg/marked,sooboy/marked,chickencoder/marked,eush77/remark,zubeio/marked,JTKnox91/marked,zubeio/marked,ekoooo/marked,zodiac-xl/marked,GerHobbelt/kramed,DigitalCoder/marked,Mignet/marked,RemiArnaud/marked,Khan/marked-react,hgGeorg/marked,dawsontoth/marked,aidenzou/marked,kumu/marked,GitbookIO/kramed,psychoss/marked,GerHobbelt/kramed,markuskobler/marked,YaqubGhazi/marked,meleslilijing/marked,bobby-brennan/marked,shovon/marked,dawsontoth/marked,chjj/marked,gjtorikian/namp,kitsonk/marked,ulrikaugustsson/mdast,yukkurisinai/mdast,papandreou/marked,dchest/marked,mrchimp/mdr-marked,treejames/marked,JTKnox91/marked,helphi/marked,aidenzou/marked,mrchimp/mdr-marked,kriskowal/marked,tanzania82/remarks,readmeio/marked,chcokr/mdast,goldenforever/nicemark,caiyongmin/marked,jonschlinkert/remarked,hyponymous/marked,kwangkim/marked-react,Jucyio/marked,hyponymous/marked,zhenghuadai/marked,Engil/marked,Engil/marked,wooorm/remark,ssbc/marked,Zhiqing-Lee/marked,huiop368/marked,segmentio/marked,aniketnandan/marked,treejames/marked,benqy/marked,nsbawden/marked,wercker/marked,meleslilijing/marked,udacity/marked,dtinth/marked,qiweiyu/marked,codydaig/marked,Mignet/marked,ericlifka/marked,vincentwoo/marked,isaacs/marked,reliefweb/marked,kangax/marked,eush77/remark,Feder1co5oave/marktex,psychoss/marked,Weasyl/marked,yxxme/marked,grant-g/marked,GitbookIO/kramed,bantic/marked,dbkaplun/marked,cadorn/marked,Baekjoon/marked,thlorenz/markdown-ast,DigitalCoder/marked,chjj/marked,markuskobler/marked,mrzie/marked,Guichaguri/marked,aroneiermann/marked,meihuabo/marked,modulexcite/marked,Ponyshow/pony-render,ekoooo/marked,webfby/marked,ssbc/marked,ShareMyWorld/marked,aniketnandan/marked,optimizely/marked,gingkoapp/marked,joaomilho/marked,yxxme/marked,papandreou/marked,codydaig/marked,Baekjoon/marked,Zhiqing-Lee/marked,vincentwoo/marked,nsbawden/marked,YaqubGhazi/marked,benqy/marked,thejameskyle/marked,InnovaCo/marked,kangax/marked,lazarofl/marked,wercker/marked