- Make fluid the default grid type
- Add default grid values, so it is demonstrable out of the gate
- Fix validation, so percentage values are accepted for gutter and padding; add more validation for widths

Introduce a 'first' marker class, since the layout builder does not operate with rows per say to allow for more inter-breakpoint flexibility so we need to specifically mark up our 'first' regions to avoid margins being applies

- Changed schema to use ints for all size values
- Changed validation to validate for ints
- Added field suffixes to explain sizes better
- Added styles to limit the form width
- Added JS to demonstrate the grid as its being edited

Allow defining a separate span prefix to allow to apply multiple breakpoint classes to a region in layout module

The basic data management, grid properties; fixed and fluid width grid examples, etc. are there.

The biggest missing piece now is the CSS generator.