* update dbft library, change to 64-bit timestamps and CV reason
* modify messages
* generate stateroot witness data from prepare* messages during commit
Fix#1273.
Using view number from the recovery message is just plain wrong, it's gonna be
higher than our current view and these messages will be treated as coming from
the future, even though they have their original view number included.
go vet is not happy about them:
pkg/io/binaryReader.go:92:21: method ReadByte() byte should have signature ReadByte() (byte, error)
pkg/io/binaryWriter.go:75:21: method WriteByte(u8 byte) should have signature WriteByte(byte) error
This seriously improves the serialization/deserialization performance for
several reasons:
* no time spent in `binary` reflection
* no memory allocations being made on every read/write
* uses fast ReadBytes everywhere it's appropriate
It also makes Fixed8 Serializable just for convenience.
Before this patch on block import we could easily be spending more than 6
seconds out of 30 in Uint256 encoding for UnspentBalance, now it's completely
off the radar.
