Wrong variables for files paths hardcoded for D7 sites

Aegir forces only D6-like variables even for D7 sites:

$conf['file_directory_path'] = 'sites/domain/files';
$conf['file_directory_temp'] = 'sites/domain/files/tmp';

It should force:

$conf['file_public_path'] = 'sites/domain/files';
$conf['file_temporary_path'] = 'sites/domain/files/tmp';

While even without correct value forced for file_public_path variable, it still works correctly with file_directory_path forced instead, the file_temporary_path will use Drupal default /tmp path, which is not what we want in the multisite environment.