Korean translation for *.psml, *.link, and folder.metadata files under the /WEB-INF/pages/**/ folder.

I added Korean strings in 71 files (*.psml, *.link, or folder.metadata), which already included Japanese or Chinese strings.
It was more difficult for me to work with xml files than with Java resource files. So I did validate the changes over and over.
I think Korean users will feel more comfortable in using JS2 by these changes.