Gives fieldsets a background color (nested fieldsets an opacity)
Adds missing scss files
Gives fieldsets a right margin so they don't flow offscreen
Merge pull request #875 from sonatype/7710_nested

Gives fieldsets a background color

+ Nested fieldsets have an opacity, so they appear darker than their parent.
+ Margins, padding, and borders have been changed as well.
Merges with master
Restricts the red outline to the right multiselector only