Add JSDoc on all block definitions.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1647 c400ca83-b69d-9dd7-9705-49c6b8615e23
Linting and JSDocs.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1648 c400ca83-b69d-9dd7-9705-49c6b8615e23
Sever dependency between context menus and dropdowns.

git-svn-id: http://blockly.googlecode.com/svn/trunk@1649 c400ca83-b69d-9dd7-9705-49c6b8615e23