Integrity testing

[glaslos]

Add more tests to verify the implementation matches the reference implementation.

[davidt99]

I'll create a script that scans a directory and compare go ssdeep and the reference ssdeep and compare the result. I'll run the script on my machine and if everything is ok, we can close this issue.

[ayoubfaouzi]

Maybe this should also run on your TravisCI tests.

[glaslos]

The initial idea was to do a one time test to confirm we align with the original implementation. But I agree we should have a continuous test to assure we don't break it in the future.

[davidt99]

I was thinking to test it in a docker container with both implementations, I'll try to get to it this week.