upgrade nodemailer; closes #439 (#440)

* upgrade nodemailer
- update documentation(s)
- add/update `package-lock.json`(s)
- add `engines` field(s)
* remove Node.js v4 from build matrix
* bump major version of node-red-node-email to v1.0.0

social/email/README.md

@@ -12,6 +12,8 @@ You will need valid email credentials for your email server.
 Install
 -------
 
+**Node.js v6 or newer is required.**
+
 Run the following command in your Node-RED user directory - typically `~/.node-red`
 
         npm i node-red-node-email

social/email/package-lock.json

@@ -0,0 +1,13 @@
+{
+  "name": "node-red-node-email",
+  "version": "0.1.29",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "nodemailer": {
+      "version": "4.6.4",
+      "resolved": "https://registry.npmjs.org/nodemailer/-/nodemailer-4.6.4.tgz",
+      "integrity": "sha512-SD4uuX7NMzZ5f5m1XHDd13J4UC3SmdJk8DsmU1g6Nrs5h3x9LcXr6EBPZIqXRJ3LrF7RdklzGhZRF/TuylTcLg=="
+    }
+  }
+}

social/email/package.json

@@ -1,12 +1,12 @@
 {
   "name": "node-red-node-email",
-  "version": "0.1.29",
+  "version": "1.0.0",
   "description": "Node-RED nodes to send and receive simple emails",
   "dependencies": {
-    "nodemailer": "^1.11.0",
-    "poplib": "^0.1.7",
+    "imap": "^0.8.19",
     "mailparser": "^0.6.2",
-    "imap": "^0.8.19"
+    "nodemailer": "^4.6.4",
+    "poplib": "^0.1.7"
   },
   "repository": {
     "type": "git",
@@ -28,5 +28,8 @@
     "name": "Dave Conway-Jones",
     "email": "ceejay@vnet.ibm.com",
     "url": "http://nodered.org"
+  },
+  "engines": {
+    "node": ">=6.0.0"
   }
 }