Whit monday is one day of for Luxembourg

[Deleted user]

Hi,

whit monday (at least for 2017 & 2018) is one day off for Luxembourg.
According to the gem it´s 2017-06-04 (which is a sunday) and 2018-05-20 (which is also a sunday).
Please check on the official homepage of Luxembourg: http://www.luxembourg.public.lu/en/travailler/jours-feries-legaux/index.html

You can even see in the tests in lu.yaml that you´re assuming that whit monday 2008 took place on 2008-05-11, which was a sunday:

Thanks,
Christian