note desired version number when already installed

install.sh

@@ -292,7 +292,7 @@ if [ -e "$node_install_path/bin/node" ]; then
     echo ""
     echo "node.js is already installed as node $($node_install_path/bin/node -v | grep v)"
     echo ""
-    echo "to reinstall please first run: rm $node_install_path/bin/node"
+    echo "to reinstall as ${NODEJS_VER} please first run: rm $node_install_path/bin/node"
     echo ""
   fi