fix: validation system

pkg/provider/acme/provider.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"crypto/tls"
 	"crypto/x509"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	fmtlog "log"
@@ -29,7 +30,6 @@ import (
 	legolog "github.com/go-acme/lego/log"
 	"github.com/go-acme/lego/providers/dns"
 	"github.com/go-acme/lego/registration"
-	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 

pkg/provider/file/file.go

@@ -3,6 +3,7 @@ package file
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -18,7 +19,6 @@ import (
 	"github.com/containous/traefik/pkg/provider"
 	"github.com/containous/traefik/pkg/safe"
 	"github.com/containous/traefik/pkg/tls"
-	"github.com/pkg/errors"
 	"gopkg.in/fsnotify.v1"
 )
 

pkg/provider/kubernetes/crd/kubernetes.go

@@ -3,6 +3,7 @@ package crd
 import (
 	"context"
 	"crypto/sha256"
+	"errors"
 	"flag"
 	"fmt"
 	"os"
@@ -20,7 +21,6 @@ import (
 	"github.com/containous/traefik/pkg/provider/kubernetes/k8s"
 	"github.com/containous/traefik/pkg/safe"
 	"github.com/containous/traefik/pkg/tls"
-	"github.com/pkg/errors"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/labels"
 )

pkg/provider/kubernetes/ingress/kubernetes.go

@@ -2,6 +2,7 @@ package ingress
 
 import (
 	"context"
+	"errors"
 	"flag"
 	"fmt"
 	"math"
@@ -19,7 +20,6 @@ import (
 	"github.com/containous/traefik/pkg/provider/kubernetes/k8s"
 	"github.com/containous/traefik/pkg/safe"
 	"github.com/containous/traefik/pkg/tls"
-	"github.com/pkg/errors"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/api/extensions/v1beta1"
 	"k8s.io/apimachinery/pkg/labels"