Remove blueimp-md5 dependency

Signed-off-by: Daan Sprenkels <hello@dsprenkels.com>

Author: Daan Sprenkels

lib/letter-avatars.js

@@ -1,6 +1,6 @@
 'use strict'
 // external modules
-const md5 = require('blueimp-md5')
+const crypto = require('crypto')
 const randomcolor = require('randomcolor')
 const config = require('./config')
 
@@ -31,15 +31,19 @@ exports.generateAvatarURL = function (name, email = '', big = true) {
     email = '' + name + '@example.com'
   }
 
+  let hash = crypto.createHash('md5')
+  hash.update(email.toLowerCase())
+  let hexDigest = hash.digest('hex')
+
   if (email !== '' && config.allowGravatar) {
-    photo = 'https://www.gravatar.com/avatar/' + md5(email.toLowerCase())
+    photo = 'https://www.gravatar.com/avatar/' + hexDigest;
     if (big) {
       photo += '?s=400'
     } else {
       photo += '?s=96'
     }
   } else {
-    photo = config.serverURL + '/user/' + (name || email.substring(0, email.lastIndexOf('@')) || md5(email.toLowerCase())) + '/avatar.svg'
+    photo = config.serverURL + '/user/' + (name || email.substring(0, email.lastIndexOf('@')) || hexDigest) + '/avatar.svg'
   }
   return photo
 }

package.json

@@ -23,7 +23,6 @@
     "aws-sdk": "^2.345.0",
     "azure-storage": "^2.7.0",
     "base64url": "^3.0.0",
-    "blueimp-md5": "^2.6.0",
     "body-parser": "^1.15.2",
     "bootstrap": "^3.3.7",
     "bootstrap-validator": "^0.11.8",