DefaultTime hide option need

[gaojianzhuang]

Sometime, we need to set the "DefaultTime" when user select date.
For example, we usually use start date and end date.
Start date as: 05/13/2016 12:00:00
End date as: 05/14/2016 23:59:59
And the "default time" should not show in the input text.

I have changed some source code for our projects, I think this feature is very common.
Could you add this feature for that ?
Thx.