If no groups, don't show header link closes https://github.com/OpenACalendar/OpenACalendar-StaticWeb-Core/issues/10
If no groups, don't show header link
closes https://github.com/OpenACalendar/OpenACalendar-StaticWeb-Core/issues/10

OpenACalendar/OpenACalendar-StaticWeb-Core,OpenACalendar/OpenACalendar-StaticWeb-Core