This commit fixes a diversion from the way the UpdateAddHTLC message is
defined within the specification. We had the HTLC expiry value in the
wrong place on the wire, which meant that we couldn’t parse the
messages as sent by the other LN implementations.
This commit updates the OnionPacketSize constant in order to reflect
the size of the onion payload as a result of the recent changes to the
sphinx packet format in the specification.
This commit modifies the Message interface to convert the Command
method to a MsgType method that uses a new set of message type for all
the defined messages. These new messages types nearly exactly match the
message types used within the current draft of the BOLT specifications.
This commit revues the Validate method from the Message interface as
the method is no longer used and is a relic from an older version of
the codebase.
