Change color of required printing of invoice and rebill instructions in Undo Multiple Bills window.

It would be nice to be able to clearly see which boxes items have already been printed in the Undo Multiple Bills window. The default grey to green is barely noticeable. Marking the checkmark turn red after printing would stand out much better. Also wording saying that the Undo Bills option will be available or no longer greyed out after the two items are printed and the checkboxes show would be helpful.