Swagger 2.0 high level model going in now

Shifting a few high level models around that are also shared. now it's just a churn game to flesh the high level model and test it up.

datamodel/high/base/xml.go

@@ -0,0 +1,35 @@
+// Copyright 2022 Princess B33f Heavy Industries / Dave Shanley
+// SPDX-License-Identifier: MIT
+
+package base
+
+import (
+	"github.com/pb33f/libopenapi/datamodel/high"
+	low "github.com/pb33f/libopenapi/datamodel/low/base"
+)
+
+type XML struct {
+	Name       string
+	Namespace  string
+	Prefix     string
+	Attribute  bool
+	Wrapped    bool
+	Extensions map[string]any
+	low        *low.XML
+}
+
+func NewXML(xml *low.XML) *XML {
+	x := new(XML)
+	x.low = xml
+	x.Name = xml.Name.Value
+	x.Namespace = xml.Namespace.Value
+	x.Prefix = xml.Namespace.Value
+	x.Attribute = xml.Attribute.Value
+	x.Wrapped = xml.Wrapped.Value
+	x.Extensions = high.ExtractExtensions(xml.Extensions)
+	return x
+}
+
+func (x *XML) GoLow() *low.XML {
+	return x.low
+}