func New(windowSize uint, maxSeq uint64) ReplayDetector {
	return &slidingWindowDetector{
		maxSeq:     maxSeq,
		windowSize: windowSize,
		mask:       newFixedBigInt(windowSize),
	}
}
New creates ReplayDetector.
Created ReplayDetector doesn't allow wrapping.
It can handle monotonically increasing sequence number up to
full 64bit number. It is suitable for DTLS replay protection.
package replaydetector
type ReplayDetector interface {
	Check(seq uint64) (accept func(), ok bool)
}
type slidingWindowDetector struct {
	latestSeq  uint64
	maxSeq     uint64
	windowSize uint
	mask       *fixedBigInt
}