Merge pull request #14 from xiaoyunwu/master

refactor TaskConfig to TaskBuilder
Merge pull request #15 from xiaoyunwu/master

Add payload rpc interface to task interface
Merge pull request #17 from xiaoyunwu/master

first reasonable full implementation of dummytask
controller: initiate etcd layout
Merge pull request #18 from fengjingchao/master

controller: initiate etcd layout
initial interface for support backup copy of a task