docs(README.md): add mention to XSS vulnerability
docs(README.md): add mention to XSS vulnerability
axter/showdown,juanonsoftware/showdown,digideskio/showdown,yaniswang/showdown,showdownjs/showdown,pazof/showdown,twitwi/showdown,OMGgogong/showdown,bsansouci/showdown,axter/showdown,bsnizek/showdown,alazyer/showdown,showdownjs/showdown,juanonsoftware/showdown,coolroad/showdown,webutilz/showdown,NichenLg/showdown,yaniswang/showdown,phw/showdown,xinshitn/showdown,stevemao/showdown,snegovick/showdown,webutilz/showdown,phw/showdown,xinshitn/showdown,digideskio/showdown,NichenLg/showdown,snegovick/showdown,coolroad/showdown,bsansouci/showdown,stevemao/showdown,alazyer/showdown,bsnizek/showdown,pazof/showdown,OMGgogong/showdown,twitwi/showdown