none:
<none>
has no related objects
<diputree> <hasline>
<none>
By default diputree has a line, none overrides this default and
effectively disables the line.
<b> <hashandle>
<none>
By default a branch has a handle, none overrides this default and effectively
disables the handle.
<b> <hasicon>
<none>
<l> <hasicon>
<none>
By default a branch/leaf has an icon, none overrides this default and
effectively disables the icon.
line compositions, handle compositions and icon compositions