Adds revisions to pages (should be there by default in screen options)

szbl-add-page-revisions.php

<?php
/*
Plugin Name: Add Page Revisions
Author: theandystratton
Author URI: http://sizeableinteractive.com
Description: Adds post type support for revisions to pages.
*/
add_action( 'init', 'szbl_add_page_revision_support' );
function szbl_add_page_revision_support()
{
	add_post_type_support( 'page', array( 'revisions', 'excerpt' ) );
}