Comment 5 for bug 1643998

Adding a note that in speaking with Eva Cerninakova, who has volunteered to serve as the translations coordinator, she identified the following languages as ones that are supported in 2.12:

Arabic (ar)
Armenian (hy)
Czech (cs)
English (Canada) (en_CA)
English (United Kingdom) (en_GB)
French (fr)
Brazilian Portuguese (pt_BR)
Spanish (es)

This adds Arabic to Ben's list (Arabic is new to 2.12) and removes Finnish. The reason behind removing Finnish is that, although there are many translated strings for Finnish, it is no longer actively maintained.