commit: Update carbon/README; test the push hooks in the xemacs-carbon2 Mercurial repo.

[Aidan Kehoe]

 Ar an tríú lá is fiche de mí na Nollaig, scríobh Aidan Kehoe: 

 > [...]

Oops; as indicated by the contents of the subject line, but not by its
prefix, that commit was to the carbon2 repository. Will fix that hook
shortly.

-- 
¿Dónde estará ahora mi sobrino Yoghurtu Nghé, que tuvo que huir
precipitadamente de la aldea por culpa de la escasez de rinocerontes?