Adding Catalan Maze.
Review URL: https://codereview.appspot.com/8040043

git-svn-id: http://blockly.googlecode.com/svn/trunk@717 c400ca83-b69d-9dd7-9705-49c6b8615e23
Adds "hide turtle" and "show turtle".
Review URL: https://codereview.appspot.com/7663053

git-svn-id: http://blockly.googlecode.com/svn/trunk@718 c400ca83-b69d-9dd7-9705-49c6b8615e23