AWAY :\r\n is not handled correctly

[slingamn]

(*Client).Away() treats the empty away message as though the client were un-away:

ergo/irc/getters.go

Lines 190 to 196 in 531a1d6

	func (client *Client) Away() (result bool, message string) {
	client.stateMutex.Lock()
	message = client.awayMessage
	client.stateMutex.Unlock()
	result = client.awayMessage != ""
	return
	}

Overall this is handled inconsistently:

AWAY :
:testnet.ergo.chat 306 shivaramtest :You have been marked as being away
whois shivaramtest
:testnet.ergo.chat 311 shivaramtest shivaramtest ~u pz43x34twmg4s.oragono * r
:testnet.ergo.chat 338 shivaramtest shivaramtest [REDACTED]
:testnet.ergo.chat 379 shivaramtest shivaramtest :is using modes +Zi
:testnet.ergo.chat 671 shivaramtest shivaramtest :is using a secure connection
:testnet.ergo.chat 317 shivaramtest shivaramtest 12 1662427209 :seconds idle, signon time
:testnet.ergo.chat 318 shivaramtest shivaramtest :End of /WHOIS list
WHO shivaramtest
:testnet.ergo.chat 352 shivaramtest * ~u pz43x34twmg4s.oragono testnet.ergo.chat shivaramtest H :0 r
:testnet.ergo.chat 315 shivaramtest shivaramtest :End of WHO list

[slingamn]

@jwheare points out that the de facto standard among server implementations is to treat an empty string parameter as "back". Our behavior is still inconsistent with the de facto standard (we send RPL_NOWAWAY in that case, even though the client is considered "back").