Added all method on user service

bin/cli-users

@@ -206,7 +206,7 @@ function listUsers() {
   const mongoose = require('../mongoose');
 
   User
-    .find()
+    .all()
     .then((users) => {
       let table = new Table({
         head: [

models/user.js

@@ -450,3 +450,11 @@ UserService.availabilityCheck = (email) => {
 UserService.count = () => {
   return UserModel.count();
 };
+
+/**
+ * Returns all the users.
+ * @return {Promise}
+ */
+UserService.all = () => {
+  return UserModel.find();
+};