WIP [VOL-2811] - Incorporate preliminary onu-adapter-go code into opencord repo

- reason "discovery-mibsync-complete" reached (via full MibUpload only, received data won't be stored yet)
- first review comments of patchset #4 considered
 (please have a look into our inline-comments in Gerrit to know more about the current state)
- no refactoring done yet

Change-Id: Iac47817f8ce4bd28dd8132f530b0570d57ae99b8
Signed-off-by: Holger Hildebrandt <holger.hildebrandt@adtran.com>
diff --git a/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
new file mode 100644
index 0000000..3ee8740
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
@@ -0,0 +1,35 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package envconfig contains grpc settings configured by environment variables.
+package envconfig
+
+import (
+	"os"
+	"strings"
+)
+
+const (
+	prefix   = "GRPC_GO_"
+	retryStr = prefix + "RETRY"
+)
+
+var (
+	// Retry is set if retry is explicitly enabled via "GRPC_GO_RETRY=on".
+	Retry = strings.EqualFold(os.Getenv(retryStr), "on")
+)