YTKNetworkfreeOPENSOURCE (The MIT License)

YTKNetwork is is a high level request util based on AFNetworking. 

- Response can be cached by expiration time

- Response can be cached by version number

- Set common base URL and CDN URL

- Validate JSON response

- Resume download

- block and delegate callback

- Batch requests 

- Chain requests

- URL filter, replace part of URL, or append common parameter

- Plugin mechanism, handle request start and finish. A plugin for show "Loading" HUD is provided