watcher error print warn

* support attachment from map[sting]string to map[string]interface{} in invocation and result

Fix: #734 

fix exporter append

Mod: Remove unnecessary return and judgement.

Fix: fix init config problem in HystrixFilter

Ftr: bitmap in router chain

Rft: Change file name to the same as interface name

Doc: modify changes.md

Rft: avoid initint the log twice 

fix: When using service discovery and provider is registered, consumer can't refresh directory