node to page: Add Pages to Page

As an alias to .Data.Pages for home page etc.

Also renamte NodeType to PageType and make it a string so it can be used in `where`.

Updates #2297

hugolib/page_permalink_test.go

@@ -66,6 +66,7 @@ func TestPermalink(t *testing.T) {
 		info := newSiteInfo(siteBuilderCfg{baseURL: string(test.base), language: helpers.NewDefaultLanguage()})
 
 		p := &Page{
+			PageType: PagePage,
 			Node: Node{
 				URLPath: URLPath{
 					Section: "z",