add failureInstanceEvent
Merge pull request #39 from xiangli-cmu/master

add failureInstanceEvent
let router know where is the contoller
add rpc for reportFailure
Merge pull request #40 from xiangli-cmu/master

let router know where is the contoller
finish demo instance
reportFailure
Merge pull request #41 from xiangli-cmu/master

reportFailure
Merge branch 'master' of github.com:go-distributed/raccoon into dev

Conflicts:
	router/router.go
Merge branch 'master' of github.com:go-distributed/raccoon into dev

Conflicts:
	router/router.go
fix report failure instance