Additonal (or user defided) date formats
The configuration page allows for a limited list of pre-defined date formats.
I would like to use a date format like "%Y-%m-%d (CW%V.%u)" to also display calendar weeks.
Is there already a way how to define that? Maybe by adding the addtional format to the right source file.
I could modify some language.yml file, but that is probably not the best solution.