mixin-column-width

@mixin column-width($fraction: $column-width-default, $persistent: false)
{
	@if $persistent {
		width: fraction-to-percentage($fraction) !important;
	}
	@else {
		width: fraction-to-percentage($fraction);
	}
	
	@if $column-breakpoint {
		@include breakpoint( $column-breakpoint ) {
			width: 100%;
		}
	}

	// /*
	//  *Remove negative margin on elements that span full width of their container
	//  */
	@if $fraction == 1/1 and $negative-right-margin {
		margin-right: 0;
	}
}