Merge pull request #33 from fengjingchao/inst

bug fixes on seq update.
Update README.md
Merge pull request #34 from yifan-gu/dev

nilStatusProcess testing covered, fixed some small bugs
Merge pull request #35 from yifan-gu/dev

cover the preparingProcess
fix test
Merge pull request #36 from fengjingchao/inst

fix test
finish replication test
set deps on immediate precessor in same instance space.
fix race cond in propose and add propose number
Merge pull request #37 from fengjingchao/inst

finish replication test
add checkpoint cycle and finish conflict replica test
Merge pull request #38 from fengjingchao/inst

add checkpoint cycle
style(replica.go, dummyTR.go)