Update sk.po

updated slovak translation
Merge pull request #170 from prescott66/patch-3

Update sk.po
Basque translation
Merge pull request #171 from asiersarasua/master

Basque translation
Update nl.po

Second attempt....
Merge pull request #173 from Pjotr123/patch-3

Update nl.po
Delete pt.mo
Update po
Add Arabic translation
Merge pull request #174 from khaledhosny/master

Add Arabic translation
Complete Arabic translation
Merge pull request #175 from khaledhosny/master

Complete Arabic translation
Allow localizing the string separator

Some languages, e.g. Arabic, use different comma than the ASCII one, so
make it localizable.
Update PO files
Update Arabic translation
Merge pull request #176 from khaledhosny/master

Allow localizing the string separator
Update it.po
Merge pull request #178 from Odysseus86/patch-1

Update it.po
Update sk.po

updated slovak translation
Update pt.po