Postfix help needed

[Stew Schneider]

I'd like to have cron jobs notify me at my gmail account when they run.
Googling around I installed mailx and postfix. The postfix installation
established main.cf as:

> # See /usr/share/postfix/main.cf.dist for a commented, more complete 
> version
>
>
> # Debian specific:  Specifying a file name will cause the first
> # line of that file to be used as the name.  The Debian default
> # is /etc/mailname.
> #myorigin = /etc/mailname
>
> smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
> biff = no
>
> # appending .domain is the MUA's job.
> append_dot_mydomain = no
>
> # Uncomment the next line to generate "delayed mail" warnings
> #delay_warning_time = 4h
>
> # TLS parameters
> smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
> smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
> smtpd_use_tls=yes
> smtpd_tls_session_cache_database = btree:${queue_directory}/smtpd_scache
> smtp_tls_session_cache_database = btree:${queue_directory}/smtp_scache
>
> # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
> # information on enabling SSL in the smtp client.
>
> myhostname = stewart
> alias_maps = hash:/etc/aliases
> alias_database = hash:/etc/aliases
> mydestination = stewart at localhost, stewart, localhost.localdomain, 
> localhost
> relayhost =
> mynetworks = 127.0.0.0/8
> mailbox_size_limit = 0
> recipient_delimiter = +
> inet_interfaces = loopback-only
The machine is not part of a domain -- it's just an elderly Gateway
sitting on a shaky desk before an elderly fat man. hostname is stewart.
I don't get no stinkin' email, and the more I Google, the confuseder I get.

Can someone untangle me?

stew