[Bf-cycles] Render All Layers in only one Render

[Eibriel]

Hi!!
1)
Is there some proposal to render all Layers in only one Render (and not 
with a "for" statement).
Something like

Render Sample
Witch Layer correspond with the Sample?
Send Sample to that Layer

With that method the background layers will have holes for the 
foreground layers, but is very useful anyway.


2)
A more specific question, is there any way to know what object (and what 
layer) correspond to every sample?

Thanks!!