spaces after command name

[Karl Berry]

    There are no spaces allowed between the command name and the opening
    brace.

1) If we make this the rule, presumably we should put it in the
manual.  (I don't see it there now.)

2) Since the very first pretesters ran into this, perhaps we should
reconsider the rule.  Regarding the "less information to keep" argument,
well, we should just declare that such spaces are completely ignored and
not kept in the XML output, ie, ignore them lexically and forget about
them.  It also seems good, in general, to avoid differences between TeX
and makeinfo when possible.

Wdyt?