(custom-nest-groups): New variable.

(custom-nest-groups): New variable.
(custom-group): Don't insert a space before the group name here.
(customize-group): If buffer exists, use it unchanged.
(custom-format-handler) <L>: Maybe make a group-link widget
instead of a group-visibility widget.
custom-nest-groups controls this.
<l, i, e>: Indent differently if custom-nest-groups.