title: has_many, belongs_to relation in active record migration rails 4
body: <p>I have a <code>User</code> model and a <code>Task</code> model. I have not mentioned any relation between them while creating them. </p>
  
  <p>I need to establish that <code>User</code> <code>has_many</code> <code>Tasks</code> and a <code>Task</code> <code>belongs_to</code> <code>User</code> through a migration  </p>
  
  <p>What would be the migration generation command for establishing that relationship?</p>