* tests: Remove if-pyramids
* tests: Switch run_command arguments
* tests: Make run_command a vararg function
* tests: Xcode doesn't obey CMake's test working directory
* openssl: move manual AES-CTR cipher into crypto init
* cmake: Move our include dir before all other include paths
This introduces a test suite for libssh2. It runs OpenSSH in a Docker
container because that works well on Windows (via docker-machine) as
well as Linux. Presumably it works on Mac too with docker-machine, but
I've not tested that.
Because the test suite is docker-machine aware, you can also run it
against a cloud provider, for more realistic network testing, by setting
your cloud provider as your active docker machine. The Appveyor CI setup
in this commit does that because Appveyor doesn't support docker
locally.