To avoid confusion, we now use 'netblock' to talk about 10.0.0.0/8,
with 10.0.0.0 being the 'prefix' and '8' being the 'prefix size'
or 'netblock size'. Use these words everywhere in the code and
documentation for clarity
Replace --sftp --scpup --scpdown by --protocol PROTOCOL.
Also take the opportunity to replace --user-any by --user * and --port-any by --port *.
All the legacy options are still supported but are now undocumented.
widest_v4_prefix (maximum allowed prefix to add in a single ACL),
and self_remote_user_only (only allow ACLs where the remote user
is the same than the bastion account name)