add node version checking and prompt (#115)

* Update binding.js

* resolve comments

lib/binding.js

@@ -2,6 +2,18 @@
 // Licensed under the MIT license.
 
 if (typeof __in_napa === 'undefined') {
+    if (process.version > 'v8.4.0' || process.version.indexOf('.') > 2) {
+        console.log('\x1b[1m\x1b[33m', 'Thanks for using Napa.js.', '\x1b[0m');
+        console.log('\x1b[1m\x1b[33m', 'There is a compatibility issue on Node v8.5.0 and above.', '\x1b[0m');
+        console.log('\x1b[1m\x1b[33m', 'We are working with Node.js team on a fix in newer Node versions.', '\x1b[0m');
+        console.log('\x1b[1m\x1b[33m', 'Please use Node with version v8.4.0 or lower.', '\x1b[0m');
+        process.exit();
+    }
+    else if (process.version < 'v4.5') {
+        console.log('\x1b[1m\x1b[33m', 'Napa.js is not supported on Node version lower than v4.5', '\x1b[0m');
+        process.exit();
+    }
+
     module.exports = require('../bin/napa-binding');
 } else {
     module.exports = process.binding('napa-binding');