Test against latest spec
Test against latest spec

postalservice14/commonmark,stof/commonmark,garethellis36/commonmark,thephpleague/commonmark,thephpleague/commonmark,bcremer/commonmark,hason/commonmark,postalservice14/commonmark,fesor/commonmark,kkiernan/commonmark,kkiernan/commonmark,fesor/commonmark,colinodell/commonmark,garethellis36/commonmark,cebe/markdown-1,hason/commonmark