add MICRO_AUTH_TOKEN, parse token in wrapper, preload config and othe… (#1261)

* add MICRO_AUTH_TOKEN, parse token in wrapper, preload config and other things

* fix wrapper panic

client/grpc/grpc.go

@@ -18,7 +18,6 @@ import (
 	"github.com/micro/go-micro/v2/errors"
 	"github.com/micro/go-micro/v2/metadata"
 	"github.com/micro/go-micro/v2/registry"
-	"github.com/micro/go-micro/v2/util/config"
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
@@ -129,10 +128,6 @@ func (g *grpcClient) call(ctx context.Context, node *registry.Node, req client.R
 	header["timeout"] = fmt.Sprintf("%d", opts.RequestTimeout)
 	// set the content type for the request
 	header["x-content-type"] = req.ContentType()
-	// set the authorization token if one is saved locally
-	if token, err := config.Get("token"); err == nil && len(token) > 0 {
-		header["authorization"] = fmt.Sprintf("Bearer %v", token)
-	}
 
 	md := gmetadata.New(header)
 	ctx = gmetadata.NewOutgoingContext(ctx, md)