(struct control): Put re_compiled member at the

(struct control): Put re_compiled member at the
end, since it's large.  Change regexpr member from char * to bool;
all uses changed.  Add new member fastmap.
(extract_regexp): regexp arg is now char const *, not char *.
Don't bother duplicating the regular expression; it's not needed.
Set fastmap from new fastmap member.  Don't bother allocating
a buffer, as the regexp code does a better job than we do.