Fixes broken link to astrodiscuss on README.md

README.md

@@ -17,7 +17,7 @@
 * [Installing Older Versions of ISIS](README.md#Installing-older-versions-of-ISIS)
 
 ## Requests for Comment
-The ISIS project uses a Request for Comment (RFC) model whereby major potential changes to the code base, data area, or binary delivery process are proposed, iterated on by any interested parties, and potentially adopted. Right now, RFCs are being housed in this repository's [wiki](https://github.com/USGS-Astrogeology/ISIS3/wiki) with associated discussions occurring on [astrodiscuss](astrodiscuss.usgs.gov).
+The ISIS project uses a Request for Comment (RFC) model whereby major potential changes to the code base, data area, or binary delivery process are proposed, iterated on by any interested parties, and potentially adopted. Right now, RFCs are being housed in this repository's [wiki](https://github.com/USGS-Astrogeology/ISIS3/wiki) with associated discussions occurring on [astrodiscuss](https://astrodiscuss.usgs.gov).
 
 Current open RFCs:
   * [Migration of ISIS Data to Git](https://github.com/USGS-Astrogeology/ISIS3/wiki/RFC4---Migration-of-ISIS-Data-to-Git)