Chore: Make NewViewDuration accept Duration-based timeouts

[meling]

The NewViewDuration expects float64 for two of its timeout inputs:

viewDuration = synchronizer.NewViewDuration(
	uint64(opts.GetTimeoutSamples()),
	float64(opts.GetInitialTimeout().AsDuration().Nanoseconds())/float64(time.Millisecond),
	float64(opts.GetMaxTimeout().AsDuration().Nanoseconds())/float64(time.Millisecond),
	float64(opts.GetTimeoutMultiplier()),
)

We should write a test for the ViewDuration implementation and change the signature from this:

func NewViewDuration(sampleSize uint64, startTimeout, maxTimeout, multiplier float64) ViewDuration {

To this:

func NewViewDuration(sampleSize uint64, multiplier float64, startTimeout, maxTimeout time.Duration) ViewDuration {