- remove python-nacl from builddeps
- add 194.patch to fix testsuite

- Update to 1.16.0:
* Added support for Ed448 host/client keys and certificates and rewrote Ed25519 support to use the PyCA implementation, reducing the dependency on libnacl and libsodium to only be needed to support the chacha20-poly1305 cipher.
* Added support for PKCS#8 format Ed25519 and Ed448 private and public keys (in addition to the OpenSSH format previously supported).
* Added support for multiple delimiters in SSHReader’s readuntil() function, causing it to return data as soon as any of the specified delimiters are matched.
* Added the ability to register custom key handlers in the line editor which can modify the input line, extending the built-in editing functionality.
* Added SSHSubprocessProtocol and SSHSubprocessTransport classes to provide compatibility with asyncio.SubprocessProtocol and asyncio.SubprocessTransport. Code which is designed to call BaseEventLoop.subprocess_shell() or BaseEventLoop.subprocess_exec() can be easily adapted to work against a remote process by calling SSHClientConnection.create_subprocess().
* Added support for sending keepalive messages when the SSH connection is idle, with an option to automatically disconnect the connection if the remote system doesn’t respond to these keepalives.
* Changed AsyncSSH to ignore errors when loading unsupported key types from the default file locations.
* Changed the reuse_port option to only be available on Python releases which support it (3.4.4 and later).
* Fixed an issue where MSG_IGNORE packets could sometimes be sent between MSG_NEWKEYS and MSG_EXT_INFO, which caused some SSH implementations to fail to properly parse the MSG_EXT_INFO.
* Fixed a couple of errors in the handling of disconnects occurring prior to authentication completing.
* Renamed “session_encoding” and “session_errors” arguments in asyncssh.create_server() to “encoding” and “errors”, to match the names used for these arguments in other AsyncSSH APIs. The old names are still supported for now, but they are marked as deprecated and will be removed in a future release.