Update libevent.h
Update libevent.h

event_del can not free the "e->rev" and "e->wev",that will leak when reconnect the redis
redis/hiredis,jinguoli/hiredis,redis/hiredis,jinguoli/hiredis,thomaslee/hiredis,thomaslee/hiredis,charsyam/hiredis,redis/hiredis,charsyam/hiredis,jinguoli/hiredis