WP Multisite fix

<?php // added in bottom of wp-config
// Allow WP_HOME and WP_SITEURL on multisite
add_filter( 'option_siteurl', function ($url) { return WP_SITEURL;} );
add_filter( 'option_home', function ($url) { return WP_HOME;});

// tell network_admin_url() to listen to WP_SITEURL
add_filter(
    'network_admin_url',
    function ($url) {
        if(substr($url, 0, strlen(WP_HOME)) !== WP_HOME)
        {
            return $url;
        }
        if(substr($url, 0, strlen(WP_SITEURL) + 1) == WP_SITEURL . '/')
        {
            return $url;
        }
        return WP_SITEURL . substr($url, strlen(WP_HOME));
    }
);