Creates a new AngularJS directive as an HTML element ov-date-time-picker to be able to create a date / time form element.

Date / time form element is composed of an AngularJS Bootstrap UI datepicker and an AngularJS Bootstrap UI timepicker.

Attributes are:

• [String] ov-current-text: The text to display for the current day button
• [String] ov-clear-text: The text to display for the clear button
• [String] ov-close-text: The text to display for the close button