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/backoff.go b/vendor/google.golang.org/grpc/backoff.go
new file mode 100644
index 0000000..ff7c3ee
--- /dev/null
+++ b/vendor/google.golang.org/grpc/backoff.go
@@ -0,0 +1,58 @@
+/*
+ *
+ * Copyright 2017 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.
+ *
+ */
+
+// See internal/backoff package for the backoff implementation. This file is
+// kept for the exported types and API backward compatibility.
+
+package grpc
+
+import (
+	"time"
+
+	"google.golang.org/grpc/backoff"
+)
+
+// DefaultBackoffConfig uses values specified for backoff in
+// https://github.com/grpc/grpc/blob/master/doc/connection-backoff.md.
+//
+// Deprecated: use ConnectParams instead. Will be supported throughout 1.x.
+var DefaultBackoffConfig = BackoffConfig{
+	MaxDelay: 120 * time.Second,
+}
+
+// BackoffConfig defines the parameters for the default gRPC backoff strategy.
+//
+// Deprecated: use ConnectParams instead. Will be supported throughout 1.x.
+type BackoffConfig struct {
+	// MaxDelay is the upper bound of backoff delay.
+	MaxDelay time.Duration
+}
+
+// ConnectParams defines the parameters for connecting and retrying. Users are
+// encouraged to use this instead of the BackoffConfig type defined above. See
+// here for more details:
+// https://github.com/grpc/grpc/blob/master/doc/connection-backoff.md.
+//
+// This API is EXPERIMENTAL.
+type ConnectParams struct {
+	// Backoff specifies the configuration options for connection backoff.
+	Backoff backoff.Config
+	// MinConnectTimeout is the minimum amount of time we are willing to give a
+	// connection to complete.
+	MinConnectTimeout time.Duration
+}