RF: createWrapper was using chmod in a way that was incompatible with macOS

share/fsl/sbin/createFSLWrapper

@@ -109,5 +109,10 @@ for script in $targets; do
   fi
 
   # Preserve file permissions
-  chmod --reference="$sourceScript" "$targetScript"
+  if [[ "$OSTYPE" == "darwin"* ]]: then
+    perms=$(stat -f "%A" "$sourceScript")
+    chmod ${perms} "$targetScript"
+  else
+    chmod --reference="$sourceScript" "$targetScript"
+  fi
 done