purpose of this plugin is, to lay out and lay in a group of consecutive layers of an image
(a humble kind of collapse and expand groups of layers)
a determinable number of layers (including the active layer) will be stored (layed out) in a new image.
the name of this image is a time stamp ("%Y%m%d-%H%M%S") plus the string ".xcf".
the visible layed out layers will be merged down to a single layer in the source image.
the name of this layer is the above mentioned time stamp.