beginners-guide-to-terraform should explain how to logon using ssh

[mjbright]

I created my first instance using this tutorial, it's really useful, thanks.

I have several comments about how this could be improved to enable an initial ssh connection.

root user for connection
It wasn't obvious to me that the authorised_key is for the 'root' user, I was trying with user 'ubuntu'
It would help to state this and/or provide an ssh example.
I propose to output the appropriate ssh commands - see below.

non-root user
Is there no way to specify a non-root user, or to at least enable authorized_keys for the existing - in this case - 'ubuntu' user ?

root password + authorized keys
It seems strange to me that we specify both - I guess this is for "safety"of not losing the ability to connect, but I would not use a password for root. Useful for debugging but maybe at least mention that it's unsafe.

output ssh connectivity info
I suggest adding some output statements as below (need to specify correct key of course)

output login_ipv4 { value = "ssh -i ~/.ssh/id_rsa root@${tolist( linode_instance.example_instance.ipv4 )[0]}" }
output ipv4 { value = linode_instance.example_instance.ipv4 }

output login_ipv6 { value = "ssh -6 -i ~/.ssh/id_rsa root@${linode_instance.example_instance.ipv6}" }
output ipv6 { value = linode_instance.example_instance.ipv6 }