Replace logCommitTick as a way to deal with revocation window exhaustion
by retrying to update the commit tx when the remote revocation is
received.
The rationale is that the revocation window always opens up because of a
revoke message that is received from the other party. It is therefore
not necessary to set a timer for this. The reception of the revoke
message is the trigger to send a new commit sig if necessary.
0b5afa64f3