Retain query and fragment URI parts from CSS src properties when packaging production.css

These get lost in production when stealing CSS, e.g:

@font-face {
  font-family: 'FontAwesome';
  src: url('../fonts/fontawesome-webfont.eot?v=4.0.3');
  src: url('../fonts/fontawesome-webfont.eot?#iefix&v=4.0.3') format('embedded-opentype'), url('../fonts/fontawesome-webfont.woff?v=4.0.3') format('woff'), url('../fonts/fontawesome-webfont.ttf?v=4.0.3') format('truetype'), url('../fonts/fontawesome-webfont.svg?v=4.0.3#fontawesomeregular') format('svg');
  font-weight: normal;
  font-style: normal;
}

... ends up as:

@font-face{font-family:'FontAwesome';src:url(../../lib/font-awesome/fonts/fontawesome-webfont.eot);src:url(../../lib/font-awesome/fonts/fontawesome-webfont.eot)... etc