difference in communication enode key and hbbft message signing key

[SurfingNerd]

version 0.8.1.

it is possible that a node has a different key for signing hbbft message than it has for the p2p communication.
this already let to problems:
it is possible that right now there are nodes out there that suffer from that problem (hbbft6?!)
It's a hard to detect problem and was the cause for Network stuck at block 91061 as well it just might be the Nr.1 (or even only reason) for Error on handling HoneyBadger message.

We need to either:

• make sure a node has defined the same key only once
• use a single point of configuration

[SurfingNerd]

it turned out that this was not the problem for hbbft6.