Edit Width
This is width in Bootstrap span terms -- a number from 1 (narrow) to 12 (full width).
You do not have to set this -- if you leave it alone, each Type has a default width. But you will
sometimes find that you prefer to have your Edit controls narrower then the default, in order to
get a good-looking Editor for a Model. Set this to a number between 1 and 12 to do that.