[iOS] block and async method unit test

mknetworkkit unit test with kiwi and ohhttpstubs

https://github.com/MugunthKumar/MKNetworkKit/blob/0b7abddf4d5063df9f922a8a4bbcb803d916195a/MKNetworkKit-Tests/MKNetworkKit-Tests/MKNetworkEngineSpec.m#L71-L113

ohhttpstubs doc

https://github.com/AliSoftware/OHHTTPStubs

kiwi doc

https://github.com/allending/Kiwi

https://github.com/allending/Kiwi/wiki

https://github.com/allending/Kiwi/wiki/Kiwi-FAQ

an article about unit test completion blocks

http://iosunittesting.com/how-to-unit-test-completion-blocks/

https://github.com/allending/Kiwi/issues/200

使用semaphore来test async method

https://github.com/icanzilb/MTTestSemaphore

http://www.touch-code-magazine.com/unit-testing-for-blocks-based-apis/

http://benwong.me/how-to-unit-test-asynchronous-methods-in-ios-using-sentestingkit/

http://samwize.com/2012/10/03/sentestingkit-does-not-support-wait-for-blocks/

http://blog.hsatac.net/2012/10/obj-c-unit-test-with-asynchronous-request/

使用runloop来test async method

http://blog.youkuaiyun.com/diyagoanyhacker/article/details/8540239

https://github.com/MagicYang/Example-Codes/tree/master/AsyncTest

http://www.wannabegeek.com/?p=245