html/template: fix documentation indent

R=nigeltao
CC=golang-dev
https://golang.org/cl/5437061

src/pkg/html/template/content.go

@@ -12,10 +12,10 @@ import (
 // Strings of content from a trusted source.
 type (
 	// CSS encapsulates known safe content that matches any of:
-	// (1) The CSS3 stylesheet production, such as `p { color: purple }`.
-	// (2) The CSS3 rule production, such as `a[href=~"https:"].foo#bar`.
-	// (3) CSS3 declaration productions, such as `color: red; margin: 2px`.
-	// (4) The CSS3 value production, such as `rgba(0, 0, 255, 127)`.
+	//   1. The CSS3 stylesheet production, such as `p { color: purple }`.
+	//   2. The CSS3 rule production, such as `a[href=~"https:"].foo#bar`.
+	//   3. CSS3 declaration productions, such as `color: red; margin: 2px`.
+	//   4. The CSS3 value production, such as `rgba(0, 0, 255, 127)`.
 	// See http://www.w3.org/TR/css3-syntax/#style
 	CSS string