protocol: closing SASL upon Unbind

[Hallvard B Furuseth <h.b.furuseth@usit.uio.no>]

protocol-28 section 4.3 (Unbind Operation) says:

> (...) close the LDAP session as follows:
>
>   - cease exchanges at the LDAP message layer,
>   - close the SASL layer (if installed),

No.  To do that, one simply closes the connection.  As I noted earlier,
[SASL] does not define the operation of closing a SASL layer, it only
defines replacing it with another layer.
I suggest

    - cease exchanges at the the SASL layer (if installed),

>   - close the TLS layer (if installed), and
>   - close the transport connection.

-- 
Hallvard