Re-stack plates in the BioStack

After the plates in the input stack have been processed, they are moved to the output stack. The Restack step moves them back into the input stack in their original order.

Important: The Restack step must be outside the "Use BioStack" loop of steps and it must follow a block. Only plates previously processed in a BioStack loop can be re-stacked. Here's an example of a Restack step in between two BioStack loops: