apple extention ios-8
https://developer.apple.com/library/prerelease/ios/documentation/General/Conceptual/ExtensibilityPG/ExtensionScenarios.html#//apple_ref/doc/uid/TP40014214-CH21-SW1 http://www.cocoawithlove.com/2009/07/simple-extensible-http-server-in-cocoa.html