Bitfinex-api-py

This fixes a minor bug in method BfxWebSocketClient::resubscribe.
**All bitfinex-api-py v3-beta's users should upgrade their projects.**

> **DISCLAIMER:** \
Production use of v3.0.0b4 (and all future beta versions) is HIGHLY discouraged. \
Beta versions should not be used in applications which require user authentication. \
Provide your API-KEY/API-SECRET, and manage your account and funds at your own risk.

* type hinting support for all API's components.
* a faster, lighter and more secure websocket client.
* several bug fixes for both http and wss interfaces.
* **...and much more!**

> **DISCLAIMER:** \
Production use of v3.0.0b3 (and all future beta versions) is HIGHLY discouraged. \
Beta versions should not be used in applications which require user authentication. \
Provide your API-KEY/API-SECRET, and manage your account and funds at your own risk.

- readme update
- refactoring improvements

* full type hinting and type checking support with mypy;
* lots of bug fixes (including critical bugs) and performance boosts;
* a new WebSocket client to ensure fast, secure and persistent connections;
* support for all 75+ REST endpoints available (including merchant endpoints);

> DISCLAIMER: \
Production use of v3.0.0b1 (and all future beta versions) is HIGHLY discouraged. \
Beta versions should not be used in applications which require user authentication. \
Provide your API-KEY/API-SECRET, and manage your account and funds at your own risk.

-) Added id field to _parse_trade

-) Show correct fees for withdraws