[Feature Request] Font path variable

Providing a font path variable would resolve common issues such as noted here: https://github.com/webpack-contrib/sass-loader#problems-with-url. As described, "bootstrap-sass for example has an $icon-font-path".

The resulting sass should be:

// var.scss
$font-path: 'fonts/' !default;

// icon.scss
@font-face {
    font-family: 'element-icons';
    src: url('#{$font-path}element-icons.eot?t=1472440741'); /* IE9*/
    src: url('#{$font-path}element-icons.woff?t=1472440741') format('woff'), /* chrome, firefox */
      url('#{$font-path}element-icons.ttf?t=1472440741') format('truetype'), /* chrome, firefox, opera, Safari, Android, iOS 4.2+*/
      url('#{$font-path}element-icons.svg?t=1472440741#el-icon') format('svg'); /* iOS 4.1- */
    font-weight: 400;
    font-style: normal;
}