Fix download link in Gmoccapy docs

Author: andypugh

docs/src/gui/gmoccapy.adoc

@@ -67,7 +67,7 @@ screens with minimum resolution of 1024x748.
 
 GMOCCAPY 3 is included in the standard distribution of LinuxCNC since release 2.8.
 So the easiest way to get GMOCCAPY on your controlling PC, is just to download the
-http://www.linuxcnc.org/index.php/english/download[ISO] and install it
+http://www.linuxcnc.org/downloads/[ISO] and install it
 from the CD/DVD/USB-stick. +
 This allows you to receive updates with the regular Debian packages.