add metro.muze.nl/details/ pages

[poef]

metrojs throws errors with a URL which is supposed to have more information about the error, causes, what to do about it, etc. These pages haven't been made yet.
Idea is to create a seperate folder in this repo, which is mapped to muze-nl.github.io/metrojs/details/, which is then also made available as metro.muze.nl/details/.