Add skin-changing callout to maze-5.  Add block-limit callout to maze-4.  Fix language pack loading in all apps (from previous CL).  Fix RTL in Turtle (also from previous CL).

R=spertus@google.com

Review URL: https://codereview.appspot.com/14064043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1385 c400ca83-b69d-9dd7-9705-49c6b8615e23