VOL-2154 : Moving back db/model to voltha-go repo

- Package imports and dockerfiles updated
- Left backend.go in voltha-lib-go

Amendments:

- Adjusted proto imports in unit tests
- Adjusted references to db/model in unit tests
- Integrate voltha-lib-go updates

Change-Id: I2d168c516a238222f0371a7bcb672d2b06796838
diff --git a/db/model/base_test.go b/db/model/base_test.go
new file mode 100644
index 0000000..45a6cdc
--- /dev/null
+++ b/db/model/base_test.go
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * 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 model
+
+import (
+	"github.com/opencord/voltha-lib-go/v2/pkg/db"
+	"github.com/opencord/voltha-lib-go/v2/pkg/log"
+	"github.com/opencord/voltha-protos/v2/go/voltha"
+	"runtime/debug"
+	"sync"
+)
+
+type ModelTestConfig struct {
+	Root      *root
+	Backend   *db.Backend
+	RootProxy *Proxy
+	DbPrefix  string
+	DbType    string
+	DbHost    string
+	DbPort    int
+	DbTimeout int
+}
+
+var callbackMutex sync.Mutex
+
+func commonChanCallback(args ...interface{}) interface{} {
+	log.Infof("Running common callback - arg count: %d", len(args))
+
+	//for i := 0; i < len(args); i++ {
+	//	log.Infof("ARG %d : %+v", i, args[i])
+	//}
+
+	callbackMutex.Lock()
+	defer callbackMutex.Unlock()
+
+	execDoneChan := args[1].(*chan struct{})
+
+	// Inform the caller that the callback was executed
+	if *execDoneChan != nil {
+		log.Infof("Sending completion indication - stack:%s", string(debug.Stack()))
+		close(*execDoneChan)
+		*execDoneChan = nil
+	}
+
+	return nil
+}
+
+func commonCallback2(args ...interface{}) interface{} {
+	log.Infof("Running common2 callback - arg count: %d %+v", len(args), args)
+
+	return nil
+}
+
+func commonCallbackFunc(args ...interface{}) interface{} {
+	log.Infof("Running common callback - arg count: %d", len(args))
+
+	for i := 0; i < len(args); i++ {
+		log.Infof("ARG %d : %+v", i, args[i])
+	}
+	execStatusFunc := args[1].(func(bool))
+
+	// Inform the caller that the callback was executed
+	execStatusFunc(true)
+
+	return nil
+}
+
+func firstCallback(args ...interface{}) interface{} {
+	name := args[0]
+	id := args[1]
+	log.Infof("Running first callback - name: %s, id: %s\n", name, id)
+	return nil
+}
+
+func secondCallback(args ...interface{}) interface{} {
+	name := args[0].(map[string]string)
+	id := args[1]
+	log.Infof("Running second callback - name: %s, id: %f\n", name["name"], id)
+	// FIXME: the panic call seem to interfere with the logging mechanism
+	//panic("Generating a panic in second callback")
+	return nil
+}
+
+func thirdCallback(args ...interface{}) interface{} {
+	name := args[0]
+	id := args[1].(*voltha.Device)
+	log.Infof("Running third callback - name: %+v, id: %s\n", name, id.Id)
+	return nil
+}