Fix Block Factory generated statement.  Issue 225.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1720 c400ca83-b69d-9dd7-9705-49c6b8615e23
Adding statement prefix to generators.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1722 c400ca83-b69d-9dd7-9705-49c6b8615e23
Add interpreter demo.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1723 c400ca83-b69d-9dd7-9705-49c6b8615e23