Layers are Inkscape way of marking top level groups. Inkscape provides
convenient UI to show and hide these groups as well as to lock them to
prevent users from accidentally editing them. Although Inkscape can open
and edit files without layers (without any top level group having the
groupmode attribute set to "layer"), it is somewhat cumbersome to move
the group created by TechDraw to a separate layer, which is what I do,
when I want to add more layers with additional information.
Signed-off-by: Łukasz Stelmach <stlman@poczta.fm>
9904d42f57