Get a DateTime object based on a random date between one given date and an interval Accepts date string that can be recognized by strtotime().

Parameters

\DateTime \| string	$date	Defaults to 30 years ago
string	$interval	Defaults to 5 days after
string \| null	$timezone	time zone in which the date time should be set, default to DateTime::$defaultTimezone, if set, otherwise the result of `date_default_timezone_get` ('1999-02-02 11:42:52', '+ 5 days')

See also: http://php.net/manual/en/timezones.php; http://php.net/manual/en/function.date-default-timezone-get.php