Change ping logic

Updated ping logic to still work when multiple lines are received from the server
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Eg. `PRIVMSG :Someuser!Someident@some.host.name PRIVMSG #channel :message\r\nPING :irc.network.org\r\n`

The current logic would send back `PONG :Someuser!Someident@some.host.name\r\n`