Salamandar/audiodev

[Salamandar]

Here is a "proper" PR. Added a commit for the cmakelists changes and cmake scripts.

[mdsitton]

So the issues previously with this PR is:
Please do better commit messages in the future. FSaudio namespace should be changed. Also I don't really want to be using error codes in the codebase so switch the current error code stuff to exceptions. use the logging library in your code as well which is doesn't currently use(though exceptions that wind their way up eventually get automatically logged). Either nuke the SDL_mixer dep or update the CMakeLists.txt to have it required. The other thing is the naming of some stuff is inconsistant with the way i've been moving things to which i can explain to you on gitter if you want.

here was my full comments from gitter:
https://gist.github.com/mdsitton/b49d9412816864392113f18a4b349892

[Salamandar]

I keep the PortAudio files "for reference" in case we would want to change back, but we could delete them ;)

[Salamandar]

Hop, changed the namespaces ! I wanted to change them while merging master into audiodev, forgot that :p