Fix Handlebars Demo's defaultPattern + Minor UIKit Tweaks

[sghoweri]

• Updates the Handlebars demo's default pattern config to fix the "empty" page that initially shows up.
• Adds a small amount of inner padding to partially address Frame size indicator and pattern Iframe padding #1062
• Reduces the global header shadow size just a tad + reduces the max logo height to make the global header's default height a bit more reasonable

[bmuenzenmeyer]

thanks for this catch! it makes sense now

[coveralls]

Coverage remained the same at 74.373% when pulling e4675f1 on fix/fix-handlebars-demo-and-small-uikit-tweaks into 3f89dda on dev.