Add route53 plugin (#1390)

* Update vendor

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Add route53 plugin

This fix adds route53 plugin so that it is possible to
query route53 record through CoreDNS.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

vendor/github.com/aws/aws-sdk-go/internal/shareddefaults/shared_config.go

@@ -0,0 +1,40 @@
+package shareddefaults
+
+import (
+	"os"
+	"path/filepath"
+	"runtime"
+)
+
+// SharedCredentialsFilename returns the SDK's default file path
+// for the shared credentials file.
+//
+// Builds the shared config file path based on the OS's platform.
+//
+//   - Linux/Unix: $HOME/.aws/credentials
+//   - Windows: %USERPROFILE%\.aws\credentials
+func SharedCredentialsFilename() string {
+	return filepath.Join(UserHomeDir(), ".aws", "credentials")
+}
+
+// SharedConfigFilename returns the SDK's default file path for
+// the shared config file.
+//
+// Builds the shared config file path based on the OS's platform.
+//
+//   - Linux/Unix: $HOME/.aws/config
+//   - Windows: %USERPROFILE%\.aws\config
+func SharedConfigFilename() string {
+	return filepath.Join(UserHomeDir(), ".aws", "config")
+}
+
+// UserHomeDir returns the home directory for the user the process is
+// running under.
+func UserHomeDir() string {
+	if runtime.GOOS == "windows" { // Windows
+		return os.Getenv("USERPROFILE")
+	}
+
+	// *nix
+	return os.Getenv("HOME")
+}

vendor/github.com/aws/aws-sdk-go/internal/shareddefaults/shared_config_other_test.go

@@ -0,0 +1,40 @@
+package shareddefaults_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/aws/aws-sdk-go/awstesting"
+	"github.com/aws/aws-sdk-go/internal/shareddefaults"
+)
+
+func TestSharedCredsFilename(t *testing.T) {
+	env := awstesting.StashEnv()
+	defer awstesting.PopEnv(env)
+
+	os.Setenv("HOME", "home_dir")
+	os.Setenv("USERPROFILE", "profile_dir")
+
+	expect := filepath.Join("home_dir", ".aws", "credentials")
+
+	name := shareddefaults.SharedCredentialsFilename()
+	if e, a := expect, name; e != a {
+		t.Errorf("expect %q shared creds filename, got %q", e, a)
+	}
+}
+
+func TestSharedConfigFilename(t *testing.T) {
+	env := awstesting.StashEnv()
+	defer awstesting.PopEnv(env)
+
+	os.Setenv("HOME", "home_dir")
+	os.Setenv("USERPROFILE", "profile_dir")
+
+	expect := filepath.Join("home_dir", ".aws", "config")
+
+	name := shareddefaults.SharedConfigFilename()
+	if e, a := expect, name; e != a {
+		t.Errorf("expect %q shared config filename, got %q", e, a)
+	}
+}

vendor/github.com/aws/aws-sdk-go/internal/shareddefaults/shared_config_windows_test.go

@@ -0,0 +1,40 @@
+package shareddefaults_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/aws/aws-sdk-go/awstesting"
+	"github.com/aws/aws-sdk-go/internal/shareddefaults"
+)
+
+func TestSharedCredsFilename(t *testing.T) {
+	env := awstesting.StashEnv()
+	defer awstesting.PopEnv(env)
+
+	os.Setenv("HOME", "home_dir")
+	os.Setenv("USERPROFILE", "profile_dir")
+
+	expect := filepath.Join("profile_dir", ".aws", "credentials")
+
+	name := shareddefaults.SharedCredentialsFilename()
+	if e, a := expect, name; e != a {
+		t.Errorf("expect %q shared creds filename, got %q", e, a)
+	}
+}
+
+func TestSharedConfigFilename(t *testing.T) {
+	env := awstesting.StashEnv()
+	defer awstesting.PopEnv(env)
+
+	os.Setenv("HOME", "home_dir")
+	os.Setenv("USERPROFILE", "profile_dir")
+
+	expect := filepath.Join("profile_dir", ".aws", "config")
+
+	name := shareddefaults.SharedConfigFilename()
+	if e, a := expect, name; e != a {
+		t.Errorf("expect %q shared config filename, got %q", e, a)
+	}
+}