title: Sequelizejs isn't showing up all the validation errors or messages
body: <p>This is my models.js</p>
  
  <pre><code>var User = require('../../managedb').User;
  
  module.exports = function(sequelize, DataTypes) {
  
  
    return sequelize.define('User', {
      username: {
        type: DataTypes.STRING,
        unique: {
          msg: "Username already exists!"
        }
      },
      password: {
        type: DataTypes.STRING,
        len: {
          args: 6,
          msg: "Password must be atleast 6 characters in length"
        }
      },
      email_id:{
        type: DataTypes.STRING,
        unique:{
          msg: "Email already exists!"
        },
        validate: {
          isEmail: {
            msg: "Email is invalid!"
          },
          notNull: true,
        }
      },
      id: {
        type: DataTypes.INTEGER,
        primaryKey: true,
        autoIncrement: true
      }
    },
      {
      instanceMethods: {
        countTasks: function() {
          // how to implement this method ?
        }
      }
    });
  </code></pre>
  
  <p>This is the error response I get when I try to save an object with a non unique username and email:</p>
  
  <pre><code>'{"length":173,"name":"error","severity":"ERROR","code":"23505","detail":"Key (email_id)=(yup2@gmail.com) already exists.","file":"nbtinsert.c","line":"397","routine":"_bt_check_unique"}'
  </code></pre>
  
  <p>Do I've to run the validate() function first? Where am I going wrong here?</p>