Add Image Dimentions

[jacobbuck]

Would be great if there was an option to add the width and height attributes to an image. And maybe background-size for svg or retina (@2x) images.

For example:

.test-png {
    background-image: url("data:image/png;base64,iVBORw0KGgoAAAAN.....");
    width: 24px;
    height: 24px;
}
.test-svg {
    background-image: url("data:image/svg+xml;base64,R0lGODlhZABkAJEA.....");
    background-size: 80px 50px;
    width: 80px;
    height: 50px;
}