Upgraded Node version to 12

Author: tsmx

README.md

@@ -14,7 +14,7 @@ AES-256-CBC encryption-at-rest for strings.
 
 ```js
 var mongoose = require('mongoose');
-const encryptedString = require('../mongoose-encryptedstring');
+const encryptedString = require('@tsmx/mongoose-encryptedstring');
 const key = 'YOUR KEY HERE';
 
 // register the new type EncryptedString

package.json

@@ -3,6 +3,10 @@
   "version": "1.0.0",
   "description": "EncryptedString type for Mongoose schemas.",
   "main": "mongoose-encryptedstring.js",
+  "engines": {
+    "node": ">=12.0.0",
+    "npm": ">=6.0.0"
+  },
   "scripts": {
     "test": "jest",
     "test-coverage": "jest --coverage",