This hacks together support for IRCv3.1 SASL. Currently only SASL PLAIN
is supported, but it's implemented in a way that adding support for
other types should not require too many changes to the current code.
Privmsgln and Privmsgf are variadic versions of the Privmsg function.
They format a message according to fmt.Sprintln and fmt.Sprintf
respectively and send it using Privmsg.
Note: Although the Privmsgln function's name infers that a new-line
character is added at the end of the message, it does not do that.
For example, the following send "golang is # 1 IMHO" to #go-nuts:
c.Privmsgln("#go-nuts", "golang is #", 1, " IMHO")
c.Privmsgf("#go-nots", "%s %d %s", "golang is #", 1, "IMHO")
* Brings logging changes to client library.
* Brings state tracker to client library.
* Rewrites all tests to use mock logger and mock state tracker.
* Makes state tracking optional, finally.
* Shaves yaks until they are almost completely bald.
