Feature/multiple date format

[BiuBiuHu]

the default order of date picker is Year - Month - Day
However some countries use Month - Day - Year format or Day-Month-Year , so we need to support more format.
refersdate format
Generally speaking, we just need change Year Month Day order , and don't need to change Hour Mins order. Because time format is always fixed.

目前在东南亚国家使用这套组件的时候，发现对本地化支持的不太好。参见日期格式。例如在泰国，我们希望的是月日年，而不是年月日，这和当地用户的使用习惯有较大差异。同时对于时间和分钟，我们却没有这样的换位需求，请参考时间格式
在查看Antd-mobile源码后发现，需要先改动rmc-date-picker，才能继续向ant-mobile提交代码，因此有了这个pull request.

[lgtm-com]

This pull request introduces 3 alerts when merging ec784b6 into e5c0e37 - view on LGTM.com

new alerts:

• 2 for Useless assignment to local variable
• 1 for Unused variable, import, function or class