Think it's done now

Altered items:
cl, require, smtpmail, smtpmail-multi-change,
smtpmail-multi-get-accounts, smtpmail-multi-send-it,
smtpmail-via-smtp, user-mail-address, smtpmail-multi
New option: smtpmail-multi-default-account

various other changes

Altered items:
smtpmail-multi-accounts, smtpmail-multi-default-account,
smtpmail-multi-associations, smtpmail-multi-change,
smtpmail-multi-get-accounts, smtpmail-multi-send-it, smtpmail-multi