SSH: Helper class to extract openssh pubkey format

Signed-off-by: Or Cohen <orc@fewbytes.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
SSH: Add authorized_keys file auth plugin

This adds support for SSH authorization via an authorized_keys file.

Signed-off-by: Or Cohen <orc@fewbytes.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
SSH: Add ec2-metadata pubkey auth plugin

This adds support for SSH authorization via the EC2 instance metadata API.

Signed-off-by: Or Cohen <orc@fewbytes.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>