Remove Blackfriday parsing from MD parse.go.
Remove Blackfriday parsing from MD parse.go.

googlecodelabs/tools,Qwiklabs/codelab-tools,Qwiklabs/codelab-tools,googlecodelabs/tools,Qwiklabs/codelab-tools,googlecodelabs/tools,googlecodelabs/tools,Qwiklabs/codelab-tools