add events package (#2341)

* add events package

* update go version

config/source/cli/cli.go

@@ -7,10 +7,10 @@ import (
 	"strings"
 	"time"
 
-	"go-micro.dev/v4/cmd"
-	"go-micro.dev/v4/config/source"
 	"github.com/imdario/mergo"
 	"github.com/urfave/cli/v2"
+	"go-micro.dev/v4/cmd"
+	"go-micro.dev/v4/config/source"
 )
 
 type cliSource struct {

config/source/cli/cli_test.go

@@ -5,11 +5,11 @@ import (
 	"os"
 	"testing"
 
+	"github.com/urfave/cli/v2"
 	"go-micro.dev/v4"
 	"go-micro.dev/v4/cmd"
 	"go-micro.dev/v4/config"
 	"go-micro.dev/v4/config/source"
-	"github.com/urfave/cli/v2"
 )
 
 func TestCliSourceDefault(t *testing.T) {

config/source/cli/options.go

@@ -3,8 +3,8 @@ package cli
 import (
 	"context"
 
-	"go-micro.dev/v4/config/source"
 	"github.com/urfave/cli/v2"
+	"go-micro.dev/v4/config/source"
 )
 
 type contextKey struct{}

config/source/env/env.go

@@ -6,8 +6,8 @@ import (
 	"strings"
 	"time"
 
-	"go-micro.dev/v4/config/source"
 	"github.com/imdario/mergo"
+	"go-micro.dev/v4/config/source"
 )
 
 var (

config/source/file/watcher.go

@@ -1,12 +1,13 @@
-//+build !linux
+//go:build !linux
+// +build !linux
 
 package file
 
 import (
 	"os"
 
-	"go-micro.dev/v4/config/source"
 	"github.com/fsnotify/fsnotify"
+	"go-micro.dev/v4/config/source"
 )
 
 type watcher struct {

config/source/file/watcher_linux.go

@@ -1,12 +1,13 @@
-//+build linux
+//go:build linux
+// +build linux
 
 package file
 
 import (
 	"os"
 
-	"go-micro.dev/v4/config/source"
 	"github.com/fsnotify/fsnotify"
+	"go-micro.dev/v4/config/source"
 )
 
 type watcher struct {

config/source/flag/flag.go

@@ -3,8 +3,8 @@ package flag
 import (
 	"errors"
 	"flag"
-	"go-micro.dev/v4/config/source"
 	"github.com/imdario/mergo"
+	"go-micro.dev/v4/config/source"
 	"strings"
 	"time"
 )

config/source/memory/memory.go

@@ -5,8 +5,8 @@ import (
 	"sync"
 	"time"
 
-	"go-micro.dev/v4/config/source"
 	"github.com/google/uuid"
+	"go-micro.dev/v4/config/source"
 )
 
 type memory struct {