Lint fixes.  Convert Turtle list variable name into messages.  Add warnings about duplicated messages in Code and Turtle.  Fix file descriptors.

R=spertus@google.com

Review URL: https://codereview.appspot.com/11618043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1121 c400ca83-b69d-9dd7-9705-49c6b8615e23