Stop plugin from adding cache headers

Add this file to your plugin folder.

<?php
    /*
    Plugin Name: Remove cache headers
    Description: Remove Cache-Control and Pragram header
    Version: 0.1
    Author: Deluxe Themes
    */
    function varnish_safe_http_headers() {
    if( !session_id() )
    {
    session_start();
    }
    header_remove ('Cache-Control');
    header_remove ("Pragma");

    }
    add_action( 'send_headers', 'varnish_safe_http_headers' );