Onboarding, Sent box and Outbox (#45)

* main

- Set

* Working

* Welcome

- Added welcome message generation

* Smtpsender

- On successful SMTP send create the "Sent" box and then
try move from "Outbox" to "Sent"

* Sent box

- Create the mailbox in `main.go` and not every time we try move from `Outbox` to `Sent`

* Use logegr

* USer

- Added logger pointer (and made use of it)
- Disallow renaming or deletion of 'Sent'

* When creating a new user set it up with logger

* Encoded message

* Added tests

* Send a welcome mail on startup (soon to mke it only happen once)

* try set flags

* Onboarding flag set

* Sender
- Removed testing code

* Welcome

- Moved welcomer code

* Cleaned up

* Added more

* renamed package

* Removed comment

* welcome

- FIxed variable names

* welcome

- Removed semi-colons
- Fixed imports

* welcome

- Ran `gofmt`

* welcome test

- Fixed up

* h

* main

- Ran `gofmt`

* Main

- Fxied

* Welcome

- Foxed name

* Added `.gitignore`

* Mailbox

- Disabled print logging

* Fixed

* fixedg

* fixe and use `%v`

internal/imapserver/backend.go

@@ -48,6 +48,7 @@ func (b *Backend) Login(conn *imap.ConnInfo, username, password string) (backend
 		backend:  b,
 		username: username,
 		conn:     conn,
+		log:			b.Log,
 	}
 	return user, nil
 }