Updated copyrights
Correct copyright formatting
new UI updates on playerbar

Signed-off-by: Seif Lotfy <seif@lotfy.com>
Fix running length when the sum is exact

When summing the total running length gives an exact number, like 2:00, show "2
min" instead of "3 min".
Added Slovenian translation
Updated POTFILES.in
Restore translations from vala branch
Updated Polish translation