Create a test folder structure

[svelderrainruiz]

As part of this effort I'm going to suggest a folder structure specific for tests. My current thought is to have a top directory called test (\test) and under that are two directories: manual (\test\manual) and unit tests (\test\unit tests).

The main reason for this is to make it more obvious where the tests are located in the structure. It also mimics what I have seen from other larger projects (ex: https://github.com/sshnet/SSH.NET).

Originally posted by @crossrulz in #73