Fixes BH-348 external service disqus.com desactivated, section is commented in case we want to implement ourselves
Translation: Exerciseboard: Clear-->Wis
Searchresults: Topic- Onderwerp, Video, Exercise-Oefening
Search results topics translation
Revert "Searchresults: Topic- Onderwerp, Video, Exercise-Oefening"

This reverts commit ddbbdaefa15121e7797455c9c496c780d7002072.
oefening vertaald
Fixes BH-346 traduction of solving_similar_triangles_1
'and' en 'or' translated (probability)
Badge translation
van mv naar ev
translation exercise
translation exercise
Fixes BH-355
Fixes BH-356
translation exercise
Update Topic Badges icons/titles with Topic Tree
Use the decimal representation for the percent answer-type in converting_decimals_to_percents.html
Revert to unset badge as retired
De mogelijke noemer iets groter gemaakt en meer kleuren gebruikt bij de hints.
Fixes error in answer message