[latexrefman] Suggestion for future update

[Karl Berry]

Hi Pablo,

    will be implemented directly at some point, you will be able to use `xparse`
    for new commands and environments, will you be able to add a comment of this in
    the future version?

Sure, we can mention xparse; I'll add something about that when I have a
chance. There will be no explanation though :). I'll just mention
whatever L3 docs I can find. I could not explain it myself in any
satisfactory way.

Thanks for the suggestion. -k