This function removes the specified layer(s) from their layer group. The layers you
pass to this function don't have to part of the same group. They are ungrouped from
whatever group they belong to. You can pass as many layers as you want to this
function. Note that as soon as a group doesn't have any more layers attached, it will
be automatically deleted.
To add layers to a group, use the GroupLayer() function. See GroupLayer for details.
You need to enable layers before you can use this function.
See Layers introduction for details.