时间相关函数

toUTCString()
toISOString()
http://www.jianshu.com/p/415f8c276388

https://segmentfault.com/a/1190000003710954?mType=Group

https://segmentfault.com/a/1190000007581722

http://www.w3school.com.cn/jsref/jsref_obj_date.asp