New features and bug fixes

- Modifications made to the request package. Planned improvements will be
sending requests on intervals, rate limiter back off support, dynamic tuning
and requests packaged into a request job group.
- Can modify each exchanges individual HTTP client (e.g timeout and
transport settings).
- Bot now uses an exchange config HTTP timeout value.
- Bot now uses a global HTTP timeout (configurable).
- Batched ticker request support for exchanges.
- Ticker and Orderbook fetching now are spanned accross multiple
go routines and regulated by a sync wait group.
- Fixes hack used to load exchanges, now uses a sync wait group.
- Ticker and Orderbook storage and fetching now uses mutex locks.
- New pair function for finding different pairs between two supplied
 pair arrays. This is used for currency pair updates for exchange which
support dynamic updating.
- Shows removal/additions of dynamic updates currencies.

exchanges/wex/wex.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"log"
-	"net/http"
 	"net/url"
 	"strconv"
 	"strings"
@@ -46,7 +45,6 @@ const (
 type WEX struct {
 	exchange.Base
 	Ticker map[string]Ticker
-	*request.Handler
 }
 
 // SetDefaults sets current default value for WEX
@@ -65,8 +63,8 @@ func (w *WEX) SetDefaults() {
 	w.ConfigCurrencyPairFormat.Uppercase = true
 	w.AssetTypes = []string{ticker.Spot}
 	w.SupportsAutoPairUpdating = false
-	w.Handler = new(request.Handler)
-	w.SetRequestHandler(w.Name, wexAuthRate, wexUnauthRate, new(http.Client))
+	w.SupportsRESTTickerBatching = true
+	w.Requester = request.New(w.Name, request.NewRateLimit(time.Second, wexAuthRate), request.NewRateLimit(time.Second, wexUnauthRate), common.NewHTTPClientWithTimeout(exchange.DefaultHTTPTimeout))
 }
 
 // Setup sets exchange configuration parameters for WEX
@@ -77,6 +75,7 @@ func (w *WEX) Setup(exch config.ExchangeConfig) {
 		w.Enabled = true
 		w.AuthenticatedAPISupport = exch.AuthenticatedAPISupport
 		w.SetAPIKeys(exch.APIKey, exch.APISecret, "", false)
+		w.SetHTTPClientTimeout(exch.HTTPTimeout)
 		w.RESTPollingDelay = exch.RESTPollingDelay
 		w.Verbose = exch.Verbose
 		w.Websocket = exch.Websocket

exchanges/wex/wex_wrapper.go

@@ -3,6 +3,7 @@ package wex
 import (
 	"errors"
 	"log"
+	"sync"
 
 	"github.com/thrasher-/gocryptotrader/common"
 	"github.com/thrasher-/gocryptotrader/currency/pair"
@@ -12,8 +13,12 @@ import (
 )
 
 // Start starts the WEX go routine
-func (w *WEX) Start() {
-	go w.Run()
+func (w *WEX) Start(wg *sync.WaitGroup) {
+	wg.Add(1)
+	go func() {
+		w.Run()
+		wg.Done()
+	}()
 }
 
 // Run implements the WEX wrapper