Ploy

------------------

* Add option ``ssh-fingerprints`` which allows to specify multiple fingerprints.
[fschulze]

* Support new output of ``ssh-keygen`` which includes the hash type and
defaults to ``SHA256``.
[fschulze]

------------------

* Allow to specify multiple masters per instance.
[fschulze]

------------------

* Add ``Executor`` helper to handle local and remote command execution. It's
also handling ssh agent forwarding enabled by either the users ssh config
or the ``ssh-extra-args`` option.
[fschulze]

------------------

* Add ``ssh-extra-args`` option.
[fschulze]

* Add ``annotate`` command to print the configuration with the source of each
setting.
[fschulze]

* Allow custom shebang in gzipped startup scripts.
[fschulze]

------------------

* Drop bad entries from our ``known_hosts`` file to prevent failures
in paramiko.
[fschulze]

* Set ``StrictHostKeyChecking=yes`` for all ssh connections to prevent
interactive asking.
[fschulze]

------------------

* Ask before terminating an instance.
[fschulze]

* Fix config setting propagation in some cases of proxied instances.
[fschulze]

* Close all connections before exiting. This prevents hangs caused by open
proxy command threads.
[fschulze]

* Add option to log debug output.
[fschulze]

* Add helpers to setup proxycommand in plugins.
[fschulze]