VM socket communication is superior to VM serial communication in
every way. Unfortunately at this time only Linux supports them.
Fortunately, that's 99% of PBot's userbase.
If you're not using Linux or if you're using an older Linux that
does not support VM sockets, the PBot VM scripts will gracefully
fallback to using the serial connection. You may explicitly
disable VM socket connection attempts by setting PBOTVM_CID=0.
