move all imports to own domain

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

codec/codec.go

@@ -1,11 +1,11 @@
 // Package codec is an interface for encoding messages
-package codec
+package codec // import "go.unistack.org/micro/v3/codec"
 
 import (
 	"errors"
 	"io"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // Message types

codec/options.go

@@ -3,9 +3,9 @@ package codec
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Option func