Change isEmpty block.

git-svn-id: http://blockly.googlecode.com/svn/trunk@663 c400ca83-b69d-9dd7-9705-49c6b8615e23
German language translations.

git-svn-id: http://blockly.googlecode.com/svn/trunk@664 c400ca83-b69d-9dd7-9705-49c6b8615e23