Gary, `@Bean` for `ftpSessionFactory` looks cool, but before it was `@ClassRule` and now it is method rule.
That means that our FtpServer resource will be reseted on each method, how ever it should be configured once for context.
So, maybe iit isn't a rule now... Maybe we should rely on `@PostConstruct` and `@PreDestroy` in the `FtpServerRule` and get rid of 
`extends ExternalResource`
WDYT?