Txrudp

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Changed
~~~~~~~
- Timeout changed to 5 seconds.

Fixed
~~~~~
- Relay address change processed before message.

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Added
~~~~~
- Add ability to change relay node on a connection.

Changed
~~~~~~~
- Switched to using ``Set`` for banned IPs.

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Added
~~~~~
- Add IP banning methods in the ConnectionMultiplexer class.

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Changed
~~~~~~~
- Check that an incoming packet is a SYN packet before creating a new connection. Prevents a connect/disconnect
loop in some error cases.

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Added
~~~~~
- Add an optional encryption layer that uses ``pynacl`` to deliver baseline confidentiality.
To take advantage of the new feature, just use ``Crypto-`` classes instead of the casual ones.
The cryptographic keys generated are meant to be used only during a single connection, for
forward secrecy. However, one can also force usage of a specific private key; see the constructor
of ``CryptoConnection`` for more details.

Changed
~~~~~~~
- Support for OSes other than Linux is currently limited because of ``pynacl``'s restricted availability.
- Update and clarify specification of sequence numbers.

Fixed
~~~~~
- Minor fixes affecting docstrings and memory usage.
- Improved packaging.

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Added
~~~~~
- Add protobuf specification and skeleton class.
- ``Connection`` now has an ``unregister`` method that simplifies detaching
the instance from the protocol. Note: The said method is *not* automatically
invoked on connection shutdown.

Changed
~~~~~~~
- Replace JSON (de)serialization with protobuf (de)serialization; reap substantial speed boost.
- Support for Python 3 is dropped until protobuf supports it too.
- packet.Packet constructor signature is no longer suitable for obtaining instances;
use the new factory methods (``from_bytes``, ``from_data``).

Fixed
~~~~~
- Corrected typos in dependency specification.