eslint: disallow "var", disallow TODO/FIXME

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ci retrigger

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errorCode safeValue → safeInteger in kuna.js ccxt#1248

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let → const in lykke.js ccxt#1211

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minor edits to handleErrors for Python safety in Kuna ccxt#1248

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Python PEP8 satisfied

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1.10.696

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1.10.695

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binance v1PostUserDataStream fix ccxt#1068

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kucoin parseOrder status fix ccxt#1240

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