check for node version

configure

@@ -11,6 +11,10 @@ if [ ! "$?" -eq 0 ]; then
 fi
 echo "Using node ${node_version}"
 
+if ! node -p 'process.exit(!/v([0-9]+)/.exec(process.version)[1] >= 4)'; then
+  echo 'Your node version is too old, use something >v4.x.x'
+fi
+
 if ! npm --version >/dev/null; then
   echo 'Node Package Manager (npm) missing'
   exit 1