DiskClient: fixed get 'Content-Disposition' header in downloadFile()
DiskClient: fixed get 'Content-Disposition' header in downloadFile()

nixsolutions/yandex-php-library,spytz/yandex-php-library,zbarinov/yandex-php-library,nixsolutions/yandex-php-library,loginwashere/yandex-php-library,loginwashere/yandex-php-library,AntonShevchuk/yandex-sdk-php,AntonShevchuk/yandex-sdk-php,zbarinov/yandex-php-library,spytz/yandex-php-library