Update DownloadScripts.java

per skrull's instructions as follows: "...As for greasefire.userscripts.org, you may want to try replacing the URLs in this file:
https://github.com/skrul/greasefire/blob/master/java/greasefire-scraper/src/com/skrul/greasefire/DownloadScripts.java
with just userscripts.org and it might just work."