WHOWAS: Show IP address and account to IRCOps.

Thanks to Noisytoot for https://github.com/unrealircd/unrealircd/pull/227
who suggested displaying account and provided a partial patch, and
armyn in https://bugs.unrealircd.org/view.php?id=6153 suggesting IP.

I chose to use the existing RPL_WHOIS* numerics that we also use for
returning WHOIS data. We already use RPL_WHOISSERVER in WHOWAS for
ages and the use of it is mentioned in RFC1459, so seems like that
was the idea right from the beginning of times. The only change I did
was from "is" to "was" in like "was logged in" and "was connecting from"
in the text of the numerics.

include/struct.h

@@ -850,8 +850,10 @@ typedef struct Whowas {
 	char *username;
 	char *hostname;
 	char *virthost;
+	char *ip;
 	char *servername;
 	char *realname;
+	char *account;
 	long umodes;
 	time_t   logoff;
 	struct Client *online;	/* Pointer to new nickname for chasing or NULL */