dispatch: store norepo/optionalrepo/inferrepo attributes in function (API) This can eliminate import cycles and ugly push/pop of global variables at _checkshellalias(). Attributes of aliascmd are directly accessible. Because norepo/optionalrepo/inferrepo lists aren't populated, extensions examining them no longer work. That's why this patch removes these lists to signal the API incompatibility. This breaks 3rd-party extensions that are yet to be ported to @command decorator.