code: function Nonce(cache, ttl) {
      this.cache = cache;
      this.ttl = ttl;
      if (this.ttl && this.ttl > TTLMAX) {
          this.ttl = TTLMAX;
      }
  }
docs: Nonce is a UUID that is created and cached until used.  When used, it is removed so that
  a request cannot perform the same action more than once.  There is a TTL on the cache, so the store
  does not continue to grow.
  
  @param cache - the hapi server cache
  @param ttl - optional, the ttl for the nonces generated
  @constructor