Rewrite os::namedsocket to use platform wrappers

[Xaymar]

Refactor the entirety of os::namedsocket to use the platform wrappers instead of direct implementations and optimize for low CPU usage and high throughput.

To Do:

• Implement Windows named-pipe (Implement os::windows::named-pipe completely #1)
• Refactor os::namedsocket code onto new platform wrappers

[Xaymar]

With the direct-read-write test done, the code seems stable enough for this to actually work now. I will have to write actual tests for each function first to determine that, otherwise my test coverage is pretty much 0 and this will take longer.