enable cache for build, closes #8 (#12)

* enable cache for build, closes #8
* goimports
* lint fixes

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util/mdns/dns_sd_test.go

@@ -3,8 +3,9 @@ package mdns
 import (
 	"reflect"
 	"testing"
+
+	"github.com/miekg/dns"
 )
-import "github.com/miekg/dns"
 
 type mockMDNSService struct{}
 

util/mdns/server.go

@@ -8,8 +8,8 @@ import (
 	"sync/atomic"
 	"time"
 
-	log "github.com/unistack-org/micro/v3/logger"
 	"github.com/miekg/dns"
+	log "github.com/unistack-org/micro/v3/logger"
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
 )