Format for clock
This is a i18n option! i18n options can not be set directly on a per-instance basis, you must include the "override" directive, and properly camel case the new name - (i.e. overrideTimeFormat). For more information, please take a look at the Localizing Datebox section.
Valid options are 12 and 24. This controls what is seen and used for the input controls, not the output format. To change the output format of the time, please see “timeOutput”.