Binance,Okx: Add Leverage, MarginType, Positions and CollateralMode support (#1220)

* init

* surprise train commit

* basic distinctions

* the terms of binance are confusing

* renames and introduction of allocatedMargin

* add new margin funcs

* pulling out wires

* implement proper getposition stuff

* bad coding day

* investigate order manager next

* a broken mess, but a progressing one

* finally completes some usdtmargined stuff

* coinMfutures eludes me

* expand to okx

* imports fix

* completes okx wrapper implementations

* cleans and polishes before rpc implementations

* rpc setup, order manager features, exch features

* more rpc, collateral and margin things

* mini test

* looking at rpc response, expansion of features

* reorganising before the storm

* changing how futures requests work

* cleanup and tests of cli usage

* remove silly client side logic

* cleanup

* collateral package, typo fix, margin err, rpc derive

* uses convert.StringToFloat ONLY ON STRUCTS FROM THIS PR

* fix binance order history bug

* niteroos

* adds new funcs to exchange standards testing

* more post merge fixes

* fix binance

* replace simepletimeformat

* fix for merge

* merge fixes

* micro fixes

* order side now required for leverage

* fix up the rest

* global -> portfolio collateral

* Update exchanges/collateral/collateral_test.go

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

* adds fields and todos

* rm field redundancy

* lint fix oopsie daisy

* fixes panic, expands error and cli explanations (sorry shaz)

* ensures casing is appropriate for underlying

* Adds a shiny TODO

---------

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

exchanges/exchange_types.go

@@ -178,13 +178,20 @@ type FeaturesSupported struct {
 // FuturesCapabilities stores the exchange's futures capabilities
 type FuturesCapabilities struct {
 	FundingRates                 bool
-	MaximumFundingRateHistory    time.Duration
-	FundingRateFrequency         time.Duration
 	Positions                    bool
 	OrderManagerPositionTracking bool
 	Collateral                   bool
 	CollateralMode               bool
 	Leverage                     bool
+	MaximumFundingRateHistory    time.Duration
+	FundingRateFrequency         time.Duration
+}
+
+// MarginCapabilities stores the exchange's margin capabilities
+type MarginCapabilities struct {
+	SetMarginType        bool
+	ChangePositionMargin bool
+	GetMarginRateHistory bool
 }
 
 // Endpoints stores running url endpoints for exchanges