Add command socket

[kostaskol]

From @leOug's AWESOME idea, the processor should be a server listening to a (unix) socket for commands (such as start, stop, recompile etc.).
This can be a bit tricky to do, as we need to explicitly have a controller thread that listens to the socket and distributes commands as needed.
Still, once implemented, this will lead us to a new (and quite exciting) direction

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To implement this, we have to split it into smaller tasks (i.e. create a command socket, re-org the main thread to also be the controlling one, etc).

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Lastly, this is blocked on #6 as it's best to have a complete working prototype before beginning a logic overhaul such as this