clearfix SASS Mixin

// http://nicolasgallagher.com/micro-clearfix-hack/
@mixin clearfix {
// For modern browsers
 &:before,
 &:after {
 content:" ";
 display:table;
 }

 &:after {
 clear:both;
 }

 // For IE 6/7 (trigger hasLayout)
 & {
 *zoom:1;
 }
}