Update autobahn to 19.9.1

[pyup-bot]

This PR updates autobahn from 19.3.3 to 19.9.1.

Changelog

19.9.1

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* new: update XBR for new contract ABIs

19.8.1

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* new: implement XBR off-chain delegate transaction signing and verification (1202)
* new: update XBR for new contract ABIs

19.7.2

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* fix: monkey patch re-add removed helper functions removed in eth-abi
* new: simple blockchain (XBR) client
* new: update XBR ABI files
* new: XBR endpoint transaction signing
* new: client side catching of WAMP URI errors in `session.call|register|publish|subscribe`

19.7.1

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* fix: implement client side payload exceed max size; improve max size exceeded handling
* fix: detect when our transport is "already" closed at connect time (1215)
* fix: XBR examples

19.6.2

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* fix: add forgotten cryptography dependency (1205)

19.6.1

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* new: XBR client library integrated (1201)
* new: add entropy depletion unit tests
* fix: make CLI tool python2 compatible (1197)
* fix: use cryptography pbkdf2 instead of custom (1198)
* fix: include tests for packaging (1194)

19.5.1

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* fix: authextra merging (1191)
* fix: set default retry_delay_jitter (1190)
* new: add rawsocket + twisted example (1189)
* new: WebSocket testing support, via Agent-style interface (1186)
* new: decorator for on_connectfailure
* fix: delayed call leakage (1152)
* new: CLI client (1150)
* fix: set up TLS over proxy properly (1149)
* new: expose ser modules (1148)
* fix: base64 encodings, add hex encoding (1146)
* new: onConnecting callback (with TransportDetails and
ConnectingRequest). **Note**: if you've implemented a pure
`IWebSocketChannel` without inheriting from Autobahn base classes,
you'll need to add an `onConnecting()` method that just does `return
None`.

Links

• PyPI: https://pypi.org/project/autobahn
• Changelog: https://pyup.io/changelogs/autobahn/
• Homepage: http://crossbar.io/autobahn

[pyup-bot]

Closing this in favor of #231