Trim space on input to make searching more robust.

R=rsc, r, gri
CC=golang-dev
https://golang.org/cl/186255

src/cmd/godoc/godoc.go

@@ -1157,7 +1157,7 @@ type SearchResult struct {
 }
 
 func search(c *http.Conn, r *http.Request) {
-	query := r.FormValue("q")
+	query := strings.TrimSpace(r.FormValue("q"))
 	var result SearchResult
 
 	if index, timestamp := searchIndex.get(); index != nil {