Capture type of Emphasis/Strong in AST

[jfrolich]

Star or Underscore. This allows parsers to treat them slightly different.

[nojb]

Actually we supported this before and I removed it because I thought it was not useful. But I'm planning to put it back since it turns out it is useful for a number of things.

[nojb]

@jfrolich On further thought could you say a few words on what use-case you have in mind for this?

[jfrolich]

For compilation to ocamldoc which has 3 emphasis/strong/bold styles.

[nojb]

You mean {e text}, {b text} and {i text} ?

[jfrolich]

Yes. I figured we could stay in the markdown spec and still support these differences.

[nojb]

I see. I am a bit reticent to adding an extra field to the AST that will be ignored most of time... On the other hand, this may come in handy for the hypothetical markdown backend, so it may be worth it after all... I will give it a shot, but am not fully convinced yet :)