message: Add unique constraint on UserId
  (for SecurityAnswer model)
diff: @@ -5,12 +5,13 @@ var insecurity = require('../lib/insecurity')
  module.exports = function (sequelize, DataTypes) {
  var SecurityAnswer = sequelize.define('SecurityAnswer', {
  - answer: DataTypes.STRING
  + answer: DataTypes.STRING,
  + UserId: {type: DataTypes.INTEGER, unique: true}
  },
  {
  classMethods: {
  associate: function (models) {
  - SecurityAnswer.belongsTo(models.User, { constraints: true, foreignKeyConstraint: true, unique: true })
  + SecurityAnswer.belongsTo(models.User)
  SecurityAnswer.belongsTo(models.SecurityQuestion, { constraints: true, foreignKeyConstraint: true })
  }
  },
  