SMTP Auth
	Preferences
		Even when AUTH is offered by the SMTP server, the user may not wish to do it.  AUTH may not be required, and be simply a bother, or AUTH may be broken and actively harmful.
		AUTH_ALLOWED - the user is willing to do auth (default ON?)
		AUTH_REQUIRED - the user wants/needs to be asked for password (default OFF)
		Username and password will be POP username and password for now.  May be reasonable to re-claim dialup username and password (by preference) in the future.
	Algorithms
		Before sending:
			if AUTH_ALLOWED && AUTH_REQUIRED
  get userŐs password
		During SMTP introductions
			if AUTH_ALLOWED && server offers AUTH && we have a password
  if auth attempt fails && AUTH_REQUIRED
    send fails
    password invalidated
		During any SMTP command
			if command returns 505
  if AUTH_ALLOWED
    set AUTH_REQUIRED
  send fails
		After SMTP session
			if send failed with 505 && !AUTH_ALLOWED
  Ask user if they want to turn on AUTH_ALLOWED
  if user wants to
    set AUTH_ALLOWED
    set AUTH_REQUIRED
	Authentication Methods Supported
		CRAM-MD5
	Example
		username: test, password: Wrloota
		Rcvd: "220 sdorner1.qualcomm.com running Eudora Internet Mail Server 2.1\r\n"
Sent: "EHLO [129.46.11.69]\r\n"
Rcvd: "250-sdorner1.qualcomm.com hello [129.46.11.69]\r\n"
Rcvd: "250-EXPN\r\n"
Rcvd: "250-PIPELINING\r\n"
Rcvd: "250-8BITMIME\r\n"
Rcvd: "250-BINARYMIME\r\n"
Rcvd: "250-CHUNKING\r\n"
Rcvd: "250-ENHANCEDSTATUSCODES\r\n"
Rcvd: "250-ETRN\r\n"
Rcvd: "250-AUTH CRAM-MD5\r\n"
Rcvd: "250 SIZE 2147483647\r\n"
Sent: "AUTH cram-md5\r\n"
Rcvd: "334 PDEzMDM4NTUyMzctMTAwNDYxMDFAc2Rvcm5lcjEucXVhbGNvbW0uY29tPg==\r\n"
Sent: "dGVzdCBhNzExODZkNDY3ZTRmNjg2NzY3NGViNzlkNWMzNWFmNw==\r\n"
Rcvd: "235 2.0.0 Authenticated\r\n"
	ImplementorŐs Notes
		Mac (Steve Dorner)
			Had to change base64 encoder to not insert linebreaks to do CRAM-MD5 properly for SMTP
			The base64 response is a base64 of the username, a space, and the hex-encoded digest, so itŐs Ňdouble-encodedÓ which seemed odd to me, but thatŐs how it is.
	References
		SMTP AUTH: <ftp://ftp.isi.edu/internet-drafts/draft-myers-smtp-auth-11.txt>
		CRAM-MD5: <ftp://ftp.isi.edu/in-notes/rfc2095.txt>
		ESMTP:  <ftp://ftp.isi.edu/in-notes/rfc1869.txt>
