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/gopkg.in/yaml.v2/README.md

@@ -67,6 +67,8 @@ b:
   d: [3, 4]
 `
 
+// Note: struct fields must be public in order for unmarshal to
+// correctly populate the data.
 type T struct {
         A string
         B struct {

vendor/gopkg.in/yaml.v2/emitterc.go

@@ -995,9 +995,9 @@ func yaml_emitter_analyze_scalar(emitter *yaml_emitter_t, value []byte) bool {
 		space_break    = false
 
 		preceded_by_whitespace = false
-		followed_by_whitespace  = false
-		previous_space          = false
-		previous_break          = false
+		followed_by_whitespace = false
+		previous_space         = false
+		previous_break         = false
 	)
 
 	emitter.scalar_data.value = value

vendor/gopkg.in/yaml.v2/example_embedded_test.go

@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"log"
 
-        "gopkg.in/yaml.v2"
+	"gopkg.in/yaml.v2"
 )
 
 // An example showing how to unmarshal embedded
@@ -17,8 +17,8 @@ type StructA struct {
 type StructB struct {
 	// Embedded structs are not treated as embedded in YAML by default. To do that,
 	// add the ",inline" annotation below
-	StructA   `yaml:",inline"`
-	B string `yaml:"b"`
+	StructA `yaml:",inline"`
+	B       string `yaml:"b"`
 }
 
 var data = `
@@ -31,11 +31,11 @@ func ExampleUnmarshal_embedded() {
 
 	err := yaml.Unmarshal([]byte(data), &b)
 	if err != nil {
-		log.Fatal("cannot unmarshal data: %v", err)
+		log.Fatalf("cannot unmarshal data: %v", err)
 	}
-        fmt.Println(b.A)
-        fmt.Println(b.B)
-        // Output:
-        // a string from struct A
-        // a string from struct B
+	fmt.Println(b.A)
+	fmt.Println(b.B)
+	// Output:
+	// a string from struct A
+	// a string from struct B
 }