more finegrained start of lease expirations (int64 -> float)
remove duplicate start of lease expiration thread
start running for election or slave_fake_prepare when entering simple paxos
fix memory leak in slaves accumulating more and more leaseExpired messages and threads
make sure lease expirations don't fire before the lease is expired
Merge pull request #189 from Incubaid/unix-time-2

Unix time 2