The '*' character can still be used for emphasis within
a word, but '_' will remain unchanged unless it starts
and ends a word.
Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
Using a '~' underline will now generate an h3 header.
A preceding overline made with the same character as the underline
is now permitted.
Signed-off-by: Kyle J. McKay <mackyle@gmail.com>