add support to revisions

<?php
/*
This snippet will add support to post revisions at event CPT
For installation instructions, see here - http://wp-events-plugin.com/tutorials/how-to-safely-add-php-code-to-wordpress/
 */
function em_mod_support($supports){
    $supports[] = 'revisions';
    return $supports;
}
add_filter('em_cp_event_supports','em_mod_support',1,1);