futures: Implement GetLatestFundingRates across exchanges (#1339)

* adds funding rate implementations and improvements

* merge fixes x1

* lint

* kucoin funding rates func make

* migrate sync-manager to keys

* some kucoin work

* adds some kucoin wrapper funcs

* ehhh, todo

* kucoin position

* start of orders

* adds the kucoin tests yay

* multiplier

* nits, EWS includes order limits

* NotYetImplemented, IsPerp improvements, cleaning

* lint, test fix, huobi time

* fixes issues, improves testing

* fixes linters I WRECKED

* local lint but remote lint, lint, lint, lint

* fixes err

* skip CI

* lint

* Supported rates, binance endpoints

* fixes weird mocktest problems

* no, CZ is invalid

* fixes some new EWS test errors

currency/code_types.go

@@ -230,6 +230,7 @@ var (
 	SSC              = NewCode("SSC")
 	SHOW             = NewCode("SHOW")
 	SPF              = NewCode("SPF")
+	PF               = NewCode("PF")
 	SNC              = NewCode("SNC")
 	SWFTC            = NewCode("SWFTC")
 	TRA              = NewCode("TRA")
@@ -3018,6 +3019,8 @@ var (
 	SWAP             = NewCode("SWAP")
 	PI               = NewCode("PI")
 	FI               = NewCode("FI")
+	USDM             = NewCode("USDM")
+	USDTM            = NewCode("USDTM")
 
 	stables = Currencies{
 		USDT,