Use sparql instead of rdql, one obscure query language is enuf thanx

rdql was used in one query but apparently no longer
supported... transformed into SPARQL instead.

mattl told me he wouldn't accept this unless I included this in my
commit message... apologies in advance.

```
       *          *
  *    _  ///\\\          *
      ( \ \\~_~|    Alright fairies
 *   (_  \_/ -' ,_   who is ready
    * / ,/  V \//     to run some
 *   (_///\   /u       SPARQL??!
     *  \\/=o=|     *
  *     (/\ | |   *
     *    /_/_/        *
         |___)_)
```
Merge pull request #1 from cwebber/remove_rdql

Use sparql instead of rdql, one obscure query language is enuf thanx.

Much ridicule was had.