btcmarkets: Add websocket orderbook checksum validation (#900)

* btcmarkets: add websocket checksum, fetch different book via REST

* Update exchanges/btcmarkets/btcmarkets_test.go

Co-authored-by: Scott <gloriousCode@users.noreply.github.com>

* buffer: add explicit type for buffer related variables and comments, do all checks buffer side and load in setup as per glorious recom.

* buffer: fix tests add error

* buffer: test re-add code cov

* depth/stream/ws: fix tests, change field name to be more specific.

* buffer: rm unused field and small comment fixes

* btcm: remove redundant field

* glorious: nits

* buffer: fix commenting

Co-authored-by: Scott <gloriousCode@users.noreply.github.com>

exchanges/bitmex/bitmex_wrapper.go

@@ -24,6 +24,7 @@ import (
 	"github.com/thrasher-corp/gocryptotrader/exchanges/protocol"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/request"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/stream"
+	"github.com/thrasher-corp/gocryptotrader/exchanges/stream/buffer"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/ticker"
 	"github.com/thrasher-corp/gocryptotrader/exchanges/trade"
 	"github.com/thrasher-corp/gocryptotrader/log"
@@ -173,7 +174,9 @@ func (b *Bitmex) Setup(exch *config.Exchange) error {
 		Unsubscriber:          b.Unsubscribe,
 		GenerateSubscriptions: b.GenerateDefaultSubscriptions,
 		Features:              &b.Features.Supports.WebsocketCapabilities,
-		UpdateEntriesByID:     true,
+		OrderbookBufferConfig: buffer.Config{
+			UpdateEntriesByID: true,
+		},
 	})
 	if err != nil {
 		return err