http://brettterpstra.com/2015/08/24/write-better-markdown/

http://spec.commonmark.org/

https://github.com/jgm/CommonMark

http://johnmacfarlane.net/babelmark2/?text=%23h1%23%0A%23%23h2%23%23%0A---%0Anormal+%60quoted%60%0Alist%3A%0A*+i1%0A*+i2%0A

http://casual-effects.com/markdeep/