Add Finnish Translation

[jere-a]

I didn't know how the list was sorted because it did not look like any sorting at all, so i added it to the end.
Should there be a like alphabetical order based of the locale code?

[marcprux]

Thanks!

I didn't know how the list was sorted because it did not look like any sorting at all […]

Yeah, the language sorting is rather chaotic right now. I plan to establish some ordering rules there soon.