tools: add import comments.

Change-Id: Idda6e64580432cb9a731e4ebf4005ee4ceb4202d
Reviewed-on: https://go-review.googlesource.com/1244
Reviewed-by: Andrew Gerrand <adg@golang.org>
diff --git a/godoc/godoc.go b/godoc/godoc.go
index 8ec731c..e77a81f 100644
--- a/godoc/godoc.go
+++ b/godoc/godoc.go
@@ -7,7 +7,7 @@
 //
 // This package comment will evolve over time as this package splits
 // into smaller pieces.
-package godoc
+package godoc // import "golang.org/x/tools/godoc"
 
 import (
 	"bytes"