Breaks webpack 2's css-loader when publicPath is an http:// url
To reproduce the bug clone https://github.com/crystalline/webfonts-loader/tree/reproduce-loader-bug
```
cd test 
yarn
node run.js
```
This produces such errors:
```
ERROR in ./~/css-loader!./~/webfonts-loader!./octicons.font.js
Module not found: Error: Can't resolve './http:/localhost:8080/9a0b787f9c5f5bf121d882c684e70901-Octicons.eot' in '/home/user/soft/webfonts-loader/test'
 @ ./~/css-loader!./~/webfonts-loader!./octicons.font.js 6:85-164
 @ ./octicons.font.js
 @ ./entry.js
```