make imce return the correct relative path

to make imce return the correct relative path, replace the function imce_relative_url in imce.module with the one below:

function imce_relative_url($path='') {
if (variable_get('file_downloads', '')==FILE_DOWNLOADS_PRIVATE) {
$file = trim(substr($path, strlen(file_directory_path())), '\\/');
return 'files'.(strlen($file) ? '/'.$file : '');
// return url('system/files').(strlen($file) ? '/'.$file : '');
}
return base_path().$path;
}