Translated Chap 4-0 to Chinese
Translated Chap4-1 Open question to Chn
Translated Chap4-2 Closed questions to chn
Translated Chap4-3 Question Working to chn
Translated Chap4-4 Designing Your Questionnaire
Finished translating Chap4
Merge pull request #2 from XiaoxiaoLi/master

Translated Chap4 to Chn