Yaml binding (#1618)

* Add YAML binding for application/x-yaml.

* Add YAML binding methods to Context.

* Review fixes.

* Revert accidentally removed import.

binding/binding_test.go

@@ -190,6 +190,9 @@ func TestBindingDefault(t *testing.T) {
 
 	assert.Equal(t, MsgPack, Default("POST", MIMEMSGPACK))
 	assert.Equal(t, MsgPack, Default("PUT", MIMEMSGPACK2))
+
+	assert.Equal(t, YAML, Default("POST", MIMEYAML))
+	assert.Equal(t, YAML, Default("PUT", MIMEYAML))
 }
 
 func TestBindingJSON(t *testing.T) {
@@ -473,6 +476,20 @@ func TestBindingXMLFail(t *testing.T) {
 		"<map><foo>bar<foo></map>", "<map><bar>foo</bar></map>")
 }
 
+func TestBindingYAML(t *testing.T) {
+	testBodyBinding(t,
+		YAML, "yaml",
+		"/", "/",
+		`foo: bar`, `bar: foo`)
+}
+
+func TestBindingYAMLFail(t *testing.T) {
+	testBodyBindingFail(t,
+		YAML, "yaml",
+		"/", "/",
+		`foo:\nbar`, `bar: foo`)
+}
+
 func createFormPostRequest() *http.Request {
 	req, _ := http.NewRequest("POST", "/?foo=getfoo&bar=getbar", bytes.NewBufferString("foo=bar&bar=foo"))
 	req.Header.Set("Content-Type", MIMEPOSTForm)