text/template: new, simpler API

The Set type is gone. Instead, templates are automatically associated by
being parsed together; nested definitions implicitly create associations.
Only associated templates can invoke one another.

This approach dramatically reduces the breadth of the construction API.

For now, html/template is deleted from src/pkg/Makefile, so this can
be checked in. Nothing in the tree depends on it. It will be updated next.

R=dsymonds, adg, rsc, r, gri, mikesamuel, nigeltao
CC=golang-dev
https://golang.org/cl/5415060
diff --git a/doc/codelab/wiki/final-noerror.go b/doc/codelab/wiki/final-noerror.go
index 53433e9..535550b 100644
--- a/doc/codelab/wiki/final-noerror.go
+++ b/doc/codelab/wiki/final-noerror.go
@@ -33,14 +33,14 @@
 	if err != nil {
 		p = &Page{Title: title}
 	}
-	t, _ := template.ParseFile("edit.html")
+	t, _ := template.ParseFiles("edit.html")
 	t.Execute(w, p)
 }
 
 func viewHandler(w http.ResponseWriter, r *http.Request) {
 	title := r.URL.Path[lenPath:]
 	p, _ := loadPage(title)
-	t, _ := template.ParseFile("view.html")
+	t, _ := template.ParseFiles("view.html")
 	t.Execute(w, p)
 }