Refactor Binance, BinanceUS and BinanceJE clients

[bmancini55]

This is a rewrite of the Binance code to support the live subscribe and remove the custom client code that used URL-based subscriptions.

The changes include:

• creation of BinanceBase that is used for all exchanges
• making BinanceBase extend BasicClient
• addition of flow control helpers for throttling, batching, and debouncing
• inclusion in the test suite of "subscribe to all markets"

This issue resolves #161

[coveralls]

Pull Request Test Coverage Report for Build a8efb43f-83c1-469e-91e9-6a1f83b69578

• 208 of 216 (96.3%) changed or added relevant lines in 7 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+4.9%) to 88.41%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/exchanges/binance-base.js	136	144	94.44%
<!--	Total:	208	216	96.3%	-->

Files with Coverage Reduction	New Missed Lines	%
src/exchanges/gemini-client.js	1	89.87%
<!--	Total:	1		-->

Totals
Change from base Build a4f6ea7a-513c-4341-866c-b90af47b062f:	4.9%
Covered Lines:	2608
Relevant Lines:	2772

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💛 - Coveralls