[WIP] EZP-21826: As an editor, I want to be able to fill date, date and time and time fields while editing a content

  :warning: Work in progress ! :warning: 
## Description

Here is the pull request about being able to fill Date, Time, DateAndTime fields in the edit part of the platformUI. Currently it's only working for the browser supporting date and time HTML5 inputs ( basically Chrome, Opera, Safari ...). 

## Screenshots

Soon available

## Link

Jira : https://jira.ez.no/browse/EZP-21826
  :warning: Work in progress ! :warning: 
the default value of the date variable should be an empty string. You can also simplify the code by writing something like:
```js
var date = '';

if (field && field.fieldValue && field.fieldValue.timestamp) {
    date = Y.Date.format(new Date(field.fieldValue.timestamp * 1000));
}
```