Adding json files from translatewiki.net.
Add file mapping Blockly keys to Closure keys.
keys.json is automatically generated by xliff_to_json.py

Review URL: https://codereview.appspot.com/9126045

git-svn-id: http://blockly.googlecode.com/svn/trunk@847 c400ca83-b69d-9dd7-9705-49c6b8615e23