[TxMt] minor bugs in Markdown bundle

[Xavier Noria]

Hello! Who is the maintainer of the bundle for Markdown? Looks like  
he is missing from the README in svn.

I noticed the regexp for emphasis

     match = "[*]([^\\\\*]|\\\\.)*?[*]";

causes the engine to beautify the bulleted list

     * normal *emph*.

with " normal " in italics instead of "emph". Do those TM regexps  
support some sort of precedence? Do they supoprt look-behind assertions?

In addition, the regexp for itemized lists looks too weak:

     begin = "^\\s*[*+-]";

According to the current spec it would be something like:

     begin = "^ {0,3}[*+-][ \\t]";

-- fxn