public static function set_server_address($server_address)
    {
        #$server_address_file = self::get_server_address_file();
        #$server_address_file->set_server_address($server_address);
        Configuration_ConfigDirectoriesHelper::make_sure_instance_specific_config_directory_exists();
        /*
         * Create the folder for the public-html module, if necessary.
         */
        $is_ph_cd = PROJECT_ROOT . DIRECTORY_SEPARATOR . 'config' . DIRECTORY_SEPARATOR . 'pubic-html';
        if (!is_dir($is_ph_cd)) {
            mkdir($is_ph_cd);
        }
        /*
         * Write the config file.
         */
        $server_address_file_name = $is_ph_cd . DIRECTORY_SEPARATOR . 'server-address.txt';
        if (is_file($server_address_file_name)) {
            unlink($server_address_file_name);
        }
        if ($fh = fopen($server_address_file_name, 'w')) {
            $server_address_file_content = <<<CNF
{$server_address}
CNF;
            fwrite($fh, $server_address_file_content);
            fclose($fh);
        }
    }
    public static function initialise_delta_files_database()
    {
        Configuration_ConfigDirectoriesHelper::make_sure_instance_specific_config_directory_exists();
        FileSystem_DirectoryHelper::mkdir_parents(self::get_delta_files_database_file_directory_name());
        $delta_files_database = new SQLiteDatabase(self::get_delta_files_database_file_name());
        $stmt = <<<SQL
CREATE TABLE
\tdelta_file_applications (
\t\tname TEXT NOT NULL UNIQUE,
\t\tmd5 TEXT,
\t\tapplied INTEGER
\t)
SQL;
        $delta_files_database->query($stmt);
    }