title: How to Add, Delete new Columns in Sequelize CLI
body: <p>I've just started using Sequelize and Sequelize CLI</p>
  
  <p>Since it's a development time, there are a frequent addition and deletion of columns. What the best the method to add a new column to an existing model?</p>
  
  <p>For example, I want to a new column '<strong>completed</strong>' to <strong>Todo</strong> model. I'll add this column to models/todo.js. Whats the next step?</p>
  
  <p>I tried <code>sequelize db:migrate</code></p>
  
  <p>not working: <em>"No migrations were executed, database schema was already up to date."</em></p>