Zepto Support

Added DateTimePicker-Zepto.js file.

You will have to use a custom build of Zepto with following Modules -

• Core Modules (zepto, event, ajax, form, ie)
• fx
• fx_methods
• data

There are some bugs because Zepto does not support all events and functions of jQuery.
Known Bugs -

• DateTimePicker is removed when you switch tab while DateTimePicker popup is open because blur event is not fired.
• TAB-key based navigation is not working since selector $("[tabIndex="+ var_tabindex + "]") is not supported. So supporting this feature atleast with current code is not possible. See Zepto Issue