func (h *Heartbeater) Heart() Heart {
	return NewSimpleHeart(h.ID, h.Location, h.interval, h.pool, h.Strategy)
}
Heart creates and returns a new instance of the Heart type with the
parameters used by the Heartbeater for consistency.
package heartbeat
import (
	"time"
	"github.com/garyburd/redigo/redis"
)
type Heartbeater struct {
	ID string
	Location string
	interval time.Duration
	pool *redis.Pool
	Strategy Strategy
}
func New(id, location string, interval time.Duration, pool *redis.Pool) *Heartbeater {
	h := &Heartbeater{
		ID:       id,
		Location: location,
		interval: interval,
		pool:     pool,
	}
	h.Strategy = HashExpireyStrategy{h.MaxAge()}
	return h
}
func (h *Heartbeater) Interval() time.Duration {
	return h.interval
}