Refactor Footnotes: Exclude footnotes heading during export, not parsing

Until now the footnotes section was parsed but not included in the resulting
AST - his required rebuilding it in the OrgWriter. It feels cleaner to include
it in the AST and only exclude it in the export

org/document.go

@@ -68,7 +68,6 @@ var DefaultFrontMatterHandler = func(k, v string) interface{} {
 func NewDocument() *Document {
 	return &Document{
 		Footnotes: &Footnotes{
-			ExcludeHeading: true,
 			Title:       "Footnotes",
 			Definitions: map[string]*FootnoteDefinition{},
 		},

org/footnote.go

@@ -5,7 +5,6 @@ import (
 )
 
 type Footnotes struct {
-	ExcludeHeading bool
 	Title       string
 	Definitions map[string]*FootnoteDefinition
 	addOrder    []string
@@ -35,8 +34,9 @@ func (d *Document) parseFootnoteDefinition(i int, parentStop stopFn) (int, Node)
 			d.tokens[i].kind == "headline" || d.tokens[i].kind == "footnoteDefinition"
 	}
 	consumed, nodes := d.parseMany(i, stop)
-	d.Footnotes.add(name, &FootnoteDefinition{name, nodes, false})
-	return consumed, nil
+	definition := FootnoteDefinition{name, nodes, false}
+	d.Footnotes.add(name, &definition)
+	return consumed, definition
 }
 
 func (fs *Footnotes) add(name string, definition *FootnoteDefinition) {

org/headline.go

@@ -68,9 +68,5 @@ func (d *Document) parseHeadline(i int, parentStop stopFn) (int, Node) {
 		}
 	}
 	headline.Children = nodes
-
-	if headline.Lvl == 1 && text == d.Footnotes.Title && d.Footnotes.ExcludeHeading {
-		return consumed + 1, nil
-	}
 	return consumed + 1, headline
 }

org/html.go

@@ -12,6 +12,7 @@ import (
 type HTMLWriter struct {
 	stringBuilder
 	HighlightCodeBlock    func(source, lang string) string
+	FootnotesHeadingTitle string
 }
 
 var emphasisTags = map[string][]string{
@@ -33,6 +34,7 @@ var listTags = map[string][]string{
 
 func NewHTMLWriter() *HTMLWriter {
 	return &HTMLWriter{
+		FootnotesHeadingTitle: "Footnotes",
 		HighlightCodeBlock: func(source, lang string) string {
 			return fmt.Sprintf("%s\n<pre>\n%s\n</pre>\n</div>", `<div class="highlight">`, html.EscapeString(source))
 		},
@@ -181,11 +183,15 @@ func (w *HTMLWriter) writeFootnotes(d *Document) {
 }
 
 func (w *HTMLWriter) writeHeadline(h Headline) {
+	title := w.nodesAsString(h.Title...)
+	if h.Lvl == 1 && title == w.FootnotesHeadingTitle {
+		return
+	}
 	w.WriteString(fmt.Sprintf("<h%d>\n", h.Lvl))
 	if h.Status != "" {
 		w.WriteString(fmt.Sprintf(`<span class="todo">%s</span>`, h.Status) + "\n")
 	}
-	w.writeNodes(h.Title...)
+	w.WriteString(title)
 	if len(h.Tags) != 0 {
 		tags := make([]string, len(h.Tags))
 		for i, tag := range h.Tags {

org/org.go

@@ -31,9 +31,7 @@ func NewOrgWriter() *OrgWriter {
 }
 
 func (w *OrgWriter) before(d *Document) {}
-func (w *OrgWriter) after(d *Document) {
-	w.writeFootnotes(d)
-}
+func (w *OrgWriter) after(d *Document)  {}
 
 func (w *OrgWriter) emptyClone() *OrgWriter {
 	wcopy := *w
@@ -160,19 +158,6 @@ func (w *OrgWriter) writeDrawer(d Drawer) {
 	w.WriteString(w.indent + ":END:\n")
 }
 
-func (w *OrgWriter) writeFootnotes(d *Document) {
-	fs := d.Footnotes
-	if len(fs.Definitions) == 0 {
-		return
-	}
-	w.WriteString("* " + fs.Title + "\n")
-	for _, definition := range fs.Ordered() {
-		if !definition.Inline {
-			w.writeNodes(definition)
-		}
-	}
-}
-
 func (w *OrgWriter) writeFootnoteDefinition(f FootnoteDefinition) {
 	w.WriteString(fmt.Sprintf("[fn:%s]", f.Name))
 	if !(len(f.Children) >= 1 && isEmptyLineParagraph(f.Children[0])) {