Add implementation comments for key rotation.
Close #290
You added this section in the implementation guidance. But I don't think you actually provide any additional implementation guidance, or? You rather provide some reasoning why 3x the largest RTO is specified and what the trade-off is. I think this would fit fine into existing Key Update section (section 4.2). More concretely, I think you can remove the first summary paragraph and simply more the second paragraph into the existing Key Update section. Or do I miss something on additional implementation guidance here?
Will try moving the text as suggested.
@mirjak Can you review again please? I think I followed your suggestion