Merge pull request #20 from yyoon/korean_update

Language: Korean update to reflect recent changes
Merge pull request #21 from yyoon/installer_korean

Korean: installer messages.
leveledit: will not print "empty" win/lose criteria (0 0 0 0 0) anymore
Fixes a bug where the advisor gives you incorrect advice when you try to hire staff without selecting a person first.
Issue 1699.

Thanks MarkL!
My check for corrupt files appear to work okay. Changed it so that it only checks some files we actually use... Also fixed the problem that you could no longer choose difficulty
Language: Dutch updated to fit all latest string changes.
Update in preparation for 0.30