Merge pull request #19 from xiaoyunwu/master

initial interface to support backup copy of task
syntax: epochID -> epoch
Merge pull request #23 from fengjingchao/syntax

syntax: epochID -> epoch
framework: init & flag meta data
comment: flag X meta ready
refactor: case-switch on string; get rid of func args
naming: testable_task.go
naming: XMetaReadyChan
refactor: one line func call
Merge pull request #22 from fengjingchao/master

framework: init & flag meta data
refactor the comminucation part, both on framework, and dummy_task