Add i18n

This just adds the individual i18n files (moved
from VisualEditor.git/lib/oojs-ui/i18n/).

I still need to add a jquery.i18n hookup. That will be optional
so that OOjs UI can be used without i18n or with a different i18n
framework if desired.

Also have the build script copy the i18n/ directory to dist/

Change-Id: I382013b523da64ccaf90c1924729feed5a3f92f4
Merge "Add i18n"