Fix the selectors

selector/blacklist/black_list_selector.go

@@ -27,7 +27,7 @@ type blackListSelector struct {
 }
 
 func init() {
-	cmd.Selectors["blacklist"] = NewSelector
+	cmd.DefaultSelectors["blacklist"] = NewSelector
 	rand.Seed(time.Now().Unix())
 }
 

selector/random/random.go

@@ -6,7 +6,7 @@ import (
 )
 
 func init() {
-	cmd.Selectors["random"] = NewSelector
+	cmd.DefaultSelectors["random"] = NewSelector
 }
 
 func NewSelector(opts ...selector.Option) selector.Selector {

selector/roundrobin/round_robin_selector.go

@@ -13,7 +13,7 @@ type roundRobinSelector struct {
 }
 
 func init() {
-	cmd.Selectors["roundrobin"] = NewSelector
+	cmd.DefaultSelectors["roundrobin"] = NewSelector
 }
 
 func (r *roundRobinSelector) Select(service string, opts ...selector.SelectOption) (selector.Next, error) {