Hardcoded path in search engine/results

Independent of http://drupal.org/node/37557 I made a patch for this problem some weeks ago and since my patch is slightly better, I submit it too.

In addition, I have some comments:
1) I recommend (strongly) using antiword in stead of catdoc. If so, you need to change the hardcoded options for "FileFilter .doc".
2) (Related to 1.) The options, and not only the executable, should be configurable for the file filters.

Thanks for a nice module.

Best regards,
Hans

PS! Improving the search result listings with subjects (author, title, description for PDF documents for example) would be great.