Naefels Trip is wrong if 'Holy Week' is in the same week

[derTobsch]

Affected country

Switzerland Glarus

Affected public holiday

Naefels Trip

Source of the information

https://www.ferienwiki.ch/feiertage/naefelser-fahrt

More information

see #635

At the moment, “Naefels Trip” is calculated as the first Thursday of April. This is incorrect, not 100% correct. If it falls within “Karwoche” (“Holy Week”). In that case, it would be on the second Thursday of April.

You could reuse “FindWeekDayInMonth” but check if the date falls between (Easter - 7 days) and Easter. If that is the case, you could just add 7 days.