* increase sentinel instance to test JedisSentinelTest
** clear() called, slave promoted to master (slave of no one), New
Sentinel force to restore it (demote) -> slave is not reusable
* ipv6 applied at Redis 2.8 -> localhost / 127.0.0.1 / ::1 is now all same
* Makefile: sleep some time for launch each sentinel (workaround to sentinel's issue)
** issue to sentinel leader vote: https://github.com/antirez/redis/issues/1419
*** sentinel may confused to vote with sentinels launched approximately same time
* remove FIXME sleep codes for Sentinel related tests
** add functions for Sentinel tests (JedisSentinelTestUtil)
*** waitForSentinelRecognizeRedisReplication
*** waitForNewPromotedMaster
*** waitForSentinelsRecognizeEachOthers
**** TODO: there're no command for sentinel to list recognized sentinel
**** sleep 5.5 sec (sentinel pings to master every 5 sec)
* set HostAndPort class to public(no longer inner) class
** reason: We cannot know pool's current master if HostAndPort class is
private inner class / HostAndPort classes are duplicated (main/test)
** make getter method and parameterized constructor
*** set fields once, get anytime
