Stefan Birkner

This PR contains the changes of #20 and #76.

I remember that there is a corner case why I didn't merge it. I start to improve Fake SFTP Server Rule next week.

I started to look at the issue again. All memory is lost.

I'm still working on it. I found that it is not as easy as I thought.

I'm working on a different API for SSH access but there are some problems. I cannot promise any date for when this will be done because my time is limited....

Can you give an example of such a failure scenario?

For simulating network failures I suggest to use a proxy that can simulate network errors. For network errors you usually don't get an answer from the SFTP server at all...

Hi @Borjianamin98, can you tell me why you want to access the internal server?

I created a new library [Fake SFTP Server Lambda](https://github.com/stefanbirkner/fake-sftp-server-lambda) that is independent of the testing framework. You can use it with TestNG.

@baubakg Does [Fake SFTP Server Lambda](https://github.com/stefanbirkner/fake-sftp-server-lambda) fix your problem?