This sub-template handle, by default, the basic functions when it is called without <format> parameter or
when the specific sub-template for the <format> doesn't exist.
Although the main object of Template:FormatDate_start_end is to present a compressed format for a range of dates
avoiding month and year redundancy, the different output formats according with each language, must be handle by an
specific sub-template.
Input parameters:
* format: name (suffix) of sub-template to build specific format
* start : property for start date of range; default is P580
* end : property for end date of range; default is P582
* place : property for qualifier of dates depicting place where happend; default is no place
* separator: digits to show between dates. default is -