Add Nodemailer and Mailgun option for contact form

controllers/contact.js

@@ -1,5 +1,17 @@
 var secrets = require('../config/secrets');
-var sendgrid  = require('sendgrid')(secrets.sendgrid.user, secrets.sendgrid.password);
+var nodemailer = require("nodemailer");
+var smtpTransport = nodemailer.createTransport("SMTP", {
+    service: "Mailgun",
+    auth: {
+        user: secrets.mailgun.login,
+        pass: secrets.mailgun.password
+    }
+    // service: "Sendgrid",
+    // auth: {
+    //     user: secrets.sendgrid.user,
+    //     pass: secrets.sendgrid.password
+    // }
+});
 
 /**
  * GET /contact
@@ -14,7 +26,7 @@ exports.getContact = function(req, res) {
 
 /**
  * POST /contact
- * Send a contact form via SendGrid.
+ * Send a contact form via Nodemailer.
  * @param email
  * @param name
  * @param message
@@ -38,14 +50,14 @@ exports.postContact = function(req, res) {
   var to = 'you@email.com';
   var subject = 'API Example | Contact Form';
 
-  var email = new sendgrid.Email({
+  var mailOptions = {
     to: to,
     from: from,
     subject: subject,
     text: body + '\n\n' + name
-  });
+  };
 
-  sendgrid.send(email, function(err) {
+  smtpTransport.sendMail(mailOptions, function(err) {
     if (err) {
       req.flash('errors', { msg: err.message });
       return res.redirect('/contact');