admin row class bug

I recently experienced a bug on the admin interface when adding an additional column to the Main row (maybe canvas). What happens is when you change the Column size. So that each column sit next to each other then save it. The top level row class gets all the row classes of each sub rows. So basically you can really get a messed up layout quickly.

I will be attaching a patch that fixes the issue as it is caused by the admin.js Pretty straight forward. Just took a bit to figure out.

-Jesse