title: Updating data UITableView
body: <p>whats the best way to refresh data in a UITableView, lets say data is populated at start-up then this data changes, how could i refresh the data, every 30 seconds or give the option of the user to refresh the data. </p>
  
  <p>i can populate data but unsure on how to update the data when it has been put in the UITableView.</p>