Support for having a 'clear' function.
Support for having a 'clear' function.

When the data-date value does not resolve to a valid Date(), the value
set in the element is cleared.

It could be better to do this _only_ if [data-date=""], happy to change
to support that.

DecipherNow/uikit,nstaeger/uikit,dimitrilongo/uikit,dimitrilongo/uikit,nstaeger/uikit,DecipherNow/uikit