How can I contribute with an updated version of the (Dutch) holidays file?

The current version for the holidays in the Netherlands is from 2012. I have modified the file that is used in the project (i18n_nl.calendar).
Where can I send this to have it integrated in the next version of GanttProject?
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Hello,
please send it to [email protected]

Hi
In order to import Israel holidays, I created an excel spreadsheet that gets it’s source from the WWW.TIMEANDDATE.COM site holiday list, and turns it into a XML that can be imported into gantproject calendar.

Is this something you might be interested in?

gordon

Please send the result file to the contact mentioned above.