Added additional layout options

Ability to have a 'centered-box', and a 'container-full' that fills the
screen with a slight gutter (half the margin that is between boxes)
Added an additional test page for layout
Form style updates, added full-width-input style

Added a form style that causes inputs, selects, and textareas to expand
to 100% width. Other style changes based around this new functionality
also added.

+ Test page updated
Commits for Tidy.css are playing up. This is an attempt to fix….
Ignore another .DS_Store