Check if a matched token is followed by a delimiter before advancing the
pointer arg. This avoids accepting composite words like "allnew" or
"defaultcontext" and misparsing them as "new" or "context".
Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>