Simple Om eka plugin to deny contributor permissions

plugin.php

<?php

add_plugin_hook('define_acl', 'deny_contributors_define_acl');

function deny_contributors_define_acl($args)
{
    $acl = $args['acl'];
    $acl->deny('contributor','Collections', array('add', 'delete-confirm', 'editSelf',
                                                   'deleteSelf', 'showSelfNotPublic'));
}

/*
 * Put this file into a directory in the /plugins directory. You can call that new plugin directory anything you want
 * Then activate the new plugin, and the contributors won't have access to creating Collections
*/