The default user expected in the connection information is the current
user, not root

With this fix, we get a friendly error message:

    failed: [localhost] => {"failed": true}
    msg: value of argument start_port is not of type int and we were unable to automatically convert

This PR adds the option to retry failed ssh executions, if the failure
is caused by ssh itself, not the remote command. This can be helpful if
there are transient network issues. Retries are only implemented in the
openssh connection plugin and are disabled by default. Retries are
enabled by setting ssh_connection > retries to an integer greater
than 0.

Running a long series of playbooks, or a short playbook against a large
cluster may result in transient ssh failures, some examples logged
[here](https://trello.com/c/1yh6csEQ/13-ssh-errors).

Ansible should be able to retry an ssh connection in order to survive
transient failures.

Ansible marks a host as failed the first time it fails to contact it.

 facts: Add ed25519 ssh pubkey 

In issue #10073 a misbehaviour in literal handling for inline lookup
arguments that can cause unexpected behaviur was reported. This
integration testcase reproduce the problem.

After applying pull request #10991 the issue is fixed and the test
passes.

Signed-off-by: Jan Losinski <losinski@wh2.tu-dresden.de>

Also fixed a bug in ssh.py where an attribute was being inappropriately
initialized in the _connect() method instead of __init__()