Add kaillera netplay support

[mxsymeg]

https://kaillerareborn.github.io/

Hopefully support for kaillera netplay can be added in subsequent releases!

[nicolasnoble]

Interesting, I didn't know about this before.

However, I spent a little bit of time exploring the project, and unfortunately, it is, quite frankly, unusable in its current state. I couldn't find any documentation whatsoever for the protocol itself, only some reverse engineered pieces here and there, some searches indicate there are multiple vulnerabilities, the "sdk" is just a Windows DLL with no source, and the two "client sources" I could find are some unusable Windows-only undocumented pieces of code.

I'm sorry, but that just won't do.

I am going to keep this issue open, in case the state of things evolves in the future, but I don't currently see any easy path forward to supporting this at the moment.