Allow template arguments to be either space separated or comma separated (simplifies build file in Blockly Games).  Upgrade angle widget's UI.

R=spertus@google.com

Review URL: https://codereview.appspot.com/41130043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1558 c400ca83-b69d-9dd7-9705-49c6b8615e23
Added clone method to field subclasses.

R=neil.fraser@gmail.com

Review URL: https://codereview.appspot.com/42030043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1559 c400ca83-b69d-9dd7-9705-49c6b8615e23
Improved comments about the optional change handler passed to
some field constructors.

R=neil.fraser@gmail.com

Review URL: https://codereview.appspot.com/42140043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1560 c400ca83-b69d-9dd7-9705-49c6b8615e23
Removing hardcoded max level constant from Maze/Plane soy files.

R=spertus@google.com

Review URL: https://codereview.appspot.com/42150043

git-svn-id: http://blockly.googlecode.com/svn/trunk@1561 c400ca83-b69d-9dd7-9705-49c6b8615e23