0.6.0

Added multiple variable assignment (by Ryan Tsao @rtsao):

@each $animal, $color in (puma, black), (sea-slug, blue) {
  .$(animal)-icon {
    background-image: url('/images/$(animal).png');
    border: 2px solid $color;
  }
}

```css
.puma-icon {
  background-image: url('/images/puma.png');
  border: 2px solid black;  
}

.sea-slug-icon {
  background-image: url('/images/sea-slug.png');
  border: 2px solid blue;
}