'cleaned up comments and added some info about the purpose of the script'

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@7077 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: gsherman

configure

@@ -1,6 +1,7 @@
 #!/bin/sh
-#CMAKE=`which xmake`
-#if [ "$CMAKE" = "" || grep -q "no xmake" "$CMAKE" ]
+# Script to check for existence of cmake and then provide
+# some moderately helpful advice on building QGIS with CMake.
+# This script doesn't actually build anything.
 NOCMAKE=0
 case $OSTYPE in
   darwin*)