handle RPC error
Merge branch 'master' of https://github.com/chenyf/push

Conflicts:
	comet/server.go
handle errors returned by control()
check if device is online
Merge branch 'master' of https://github.com/chenyf/push
rename sso_tk to token
change MQ RPC from fanout to direct
add the API to check online devices
Merge pull request #18 from zhengzhiren/master

merge