The new category manager has strong encoding issues, at least for French characters. The issues appear both when it reads old categories and when new ones are created. It produces an inconsistent behaviour in which multiple errors make the categories unusable (see below).

Reproducible: Always

Steps to Reproduce:
1. Have a category called "Réunion" or create a new one
2. The category appears as "R###union" where ### stands for "weird characters"
3. Apply the "R###union" to a new event
4. The new event is not colored according to the category

Actual Results:  
When opening its details, its category is in fact "R######union" where the weird characters have been duplicated

Expected Results:  
The event should be colored accordingly to its category. At least, its category should be "R######union", at best, we would expect to have French character support and get "Réunion" (though it consider it minor compared to the first expectation).