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/ro_core/core/core.go b/ro_core/core/core.go
index c98e891..45bbde2 100644
--- a/ro_core/core/core.go
+++ b/ro_core/core/core.go
@@ -17,9 +17,10 @@
 
 import (
 	"context"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-go/ro_core/config"
+	"github.com/opencord/voltha-lib-go/v2/pkg/db"
 	"github.com/opencord/voltha-lib-go/v2/pkg/db/kvstore"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
 	grpcserver "github.com/opencord/voltha-lib-go/v2/pkg/grpc"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-lib-go/v2/pkg/probe"
@@ -58,7 +59,7 @@
 	// Do not call NewBackend constructor; it creates its own KV client
 	// Commented the backend for now until the issue between the model and the KV store
 	// is resolved.
-	backend := model.Backend{
+	backend := db.Backend{
 		Client:     kvClient,
 		StoreType:  cf.KVStoreType,
 		Host:       cf.KVStoreHost,
diff --git a/ro_core/core/device_agent.go b/ro_core/core/device_agent.go
index a1d643d..63af020 100644
--- a/ro_core/core/device_agent.go
+++ b/ro_core/core/device_agent.go
@@ -18,7 +18,7 @@
 import (
 	"context"
 	"github.com/gogo/protobuf/proto"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"google.golang.org/grpc/codes"
diff --git a/ro_core/core/device_agent_test.go b/ro_core/core/device_agent_test.go
index f8d8d45..bb87fac 100644
--- a/ro_core/core/device_agent_test.go
+++ b/ro_core/core/device_agent_test.go
@@ -16,8 +16,9 @@
 package core
 
 import (
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-go/ro_core/config"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-lib-go/v2/pkg/db"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"github.com/stretchr/testify/assert"
 	"testing"
@@ -28,7 +29,7 @@
 	var core Core
 	core.instanceId = "ro_core"
 	core.config = config.NewROCoreFlags()
-	backend := model.Backend{
+	backend := db.Backend{
 		Client:     core.kvClient,
 		StoreType:  core.config.KVStoreType,
 		Host:       core.config.KVStoreHost,
diff --git a/ro_core/core/device_manager.go b/ro_core/core/device_manager.go
index f853730..fd69705 100644
--- a/ro_core/core/device_manager.go
+++ b/ro_core/core/device_manager.go
@@ -17,7 +17,7 @@
 
 import (
 	"context"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-lib-go/v2/pkg/probe"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
diff --git a/ro_core/core/device_manager_test.go b/ro_core/core/device_manager_test.go
index 3959f44..cef848c 100644
--- a/ro_core/core/device_manager_test.go
+++ b/ro_core/core/device_manager_test.go
@@ -16,8 +16,9 @@
 package core
 
 import (
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-go/ro_core/config"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-lib-go/v2/pkg/db"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"github.com/stretchr/testify/assert"
 	"testing"
@@ -27,7 +28,7 @@
 	var core Core
 	core.instanceId = "ro_core"
 	core.config = config.NewROCoreFlags()
-	backend := model.Backend{
+	backend := db.Backend{
 		Client:     core.kvClient,
 		StoreType:  core.config.KVStoreType,
 		Host:       core.config.KVStoreHost,
diff --git a/ro_core/core/logical_device_agent.go b/ro_core/core/logical_device_agent.go
index 8d14806..635379a 100644
--- a/ro_core/core/logical_device_agent.go
+++ b/ro_core/core/logical_device_agent.go
@@ -18,7 +18,7 @@
 import (
 	"context"
 	"github.com/gogo/protobuf/proto"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"google.golang.org/grpc/codes"
diff --git a/ro_core/core/logical_device_manager.go b/ro_core/core/logical_device_manager.go
index 586598d..57eb7bc 100644
--- a/ro_core/core/logical_device_manager.go
+++ b/ro_core/core/logical_device_manager.go
@@ -17,7 +17,7 @@
 
 import (
 	"context"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-lib-go/v2/pkg/probe"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
diff --git a/ro_core/core/model_proxy.go b/ro_core/core/model_proxy.go
index f663572..7f78a5d 100644
--- a/ro_core/core/model_proxy.go
+++ b/ro_core/core/model_proxy.go
@@ -17,7 +17,7 @@
 
 import (
 	"context"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
diff --git a/ro_core/core/model_proxy_manager.go b/ro_core/core/model_proxy_manager.go
index 23261f5..fcf1c78 100644
--- a/ro_core/core/model_proxy_manager.go
+++ b/ro_core/core/model_proxy_manager.go
@@ -18,7 +18,7 @@
 import (
 	"context"
 	"encoding/json"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-lib-go/v2/pkg/log"
 	"github.com/opencord/voltha-lib-go/v2/pkg/version"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
diff --git a/ro_core/core/model_proxy_test.go b/ro_core/core/model_proxy_test.go
index 6cd9f65..8215fb8 100644
--- a/ro_core/core/model_proxy_test.go
+++ b/ro_core/core/model_proxy_test.go
@@ -17,7 +17,7 @@
 
 import (
 	"context"
-	"github.com/opencord/voltha-lib-go/v2/pkg/db/model"
+	"github.com/opencord/voltha-go/db/model"
 	"github.com/opencord/voltha-protos/v2/go/voltha"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"