Update locales-fi-FI.xml

Added missing translations and corrected few minor mistakes. Also changed term "suomentaja" to "kääntäjä". Kääntäjä means translator. "Suomentaja" is person who translates something to finnish. Fixed also form of presenting months in dates.
Update locales-fi-FI.xml

Fixed error which prevented validating.
Update locales-fi-FI.xml

translator short form fixed from suom. to käänt.
Merge pull request #73 from snissine/patch-1

Update locales-fi-FI.xml