message: support for root-relative path
diff: import { Resource } from 'resource-loader';
  -import path from 'path';
  +import url from 'url';
  import { Spritesheet } from '../core';
  export default function ()
  @@ -35,7 +35,7 @@ export default function ()
  }
  else
  {
  - resourcePath = `${path.dirname(resource.url.replace(this.baseUrl, ''))}/${resource.data.meta.image}`;
  + resourcePath = url.resolve(resource.url.replace(this.baseUrl, ''), resource.data.meta.image);
  }
  // load the image for this sheet
  