Refactored decoder responsibilities (#1402)

- improved comment handling
- yaml decoder now responsible for leading content work around

pkg/yqlib/lib.go

@@ -248,14 +248,16 @@ func guessTagFromCustomType(node *yaml.Node) string {
 }
 
 func parseSnippet(value string) (*yaml.Node, error) {
-	decoder := NewYamlDecoder()
-	decoder.Init(strings.NewReader(value))
-	var dataBucket yaml.Node
-	err := decoder.Decode(&dataBucket)
-	if len(dataBucket.Content) == 0 {
+	decoder := NewYamlDecoder(ConfiguredYamlPreferences)
+	err := decoder.Init(strings.NewReader(value))
+	if err != nil {
+		return nil, err
+	}
+	parsedNode, err := decoder.Decode()
+	if len(parsedNode.Node.Content) == 0 {
 		return nil, fmt.Errorf("bad data")
 	}
-	return dataBucket.Content[0], err
+	return unwrapDoc(parsedNode.Node), err
 }
 
 func recursiveNodeEqual(lhs *yaml.Node, rhs *yaml.Node) bool {