This formats a moment object into a date string according to the string format that is desired.
Usage:
{{moment-format momentObject 'DD-MM-YYYY'}} <!--returns "01-01-1970"-->
Parameters:
- momentObject - a moment object (either in a model with moment-date attr, or selected by bs-datetimepicker)
- format - This tells the helper how the date should be returned as a string. For codes for the string format, click here for Moment.js string format.