Resolve "Refactor the name of our own error package to prevent issues with the go errors package"

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Closes #250 (closed)

cli/adapter/PndAdapter.go

@@ -7,8 +7,8 @@ import (
 	ppb "code.fbi.h-da.de/danet/gosdn/api/go/gosdn/pnd"
 	tpb "code.fbi.h-da.de/danet/gosdn/api/go/gosdn/transport"
 	"code.fbi.h-da.de/danet/gosdn/controller/api"
+	"code.fbi.h-da.de/danet/gosdn/controller/customerrs"
 	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/southbound"
-	"code.fbi.h-da.de/danet/gosdn/controller/nucleus/errors"
 	"github.com/google/uuid"
 	"github.com/openconfig/goyang/pkg/yang"
 	"golang.org/x/sync/errgroup"
@@ -37,12 +37,12 @@ func NewPndAdapter(id, endpoint string) (*PndAdapter, error) {
 
 // AddSbi adds an SBI to the PND Adapter. Currently not implemented.
 func (p *PndAdapter) AddSbi(s southbound.SouthboundInterface) error {
-	return &errors.ErrNotYetImplemented{}
+	return &customerrs.NotYetImplementedError{}
 }
 
 // RemoveSbi removes an SBI from the PND Adapter. Currently not implemented.
 func (p *PndAdapter) RemoveSbi(uuid.UUID) error {
-	return &errors.ErrNotYetImplemented{}
+	return &customerrs.NotYetImplementedError{}
 }
 
 // AddDevice adds a new device to the controller. The device name is optional.