Fix some oversights of \layout in \book (issue 10794044)

[thomasmorley65]

Reviewers: ,

Message:
Please review.

Description:
Fix some oversights of \layout in \book

follow-up for issue 3151

Please review this at https://codereview.appspot.com/10794044/

Affected files:
  M Documentation/notation/input.itely


Index: Documentation/notation/input.itely
diff --git a/Documentation/notation/input.itely  
b/Documentation/notation/input.itely
index  
4381f68af39cbcddee5ecb05fc4d7199b96c1abb..0929c21801df0d3caf744113b534036309fcec74  
100644
--- a/Documentation/notation/input.itely
+++ b/Documentation/notation/input.itely
@@ -243,15 +243,15 @@ name which may clash, so
 @example
 \book @{
   \score @{ @dots{} @}
-  \layout @{ @dots{} @}
+  \paper @{ @dots{} @}
 @}
 \book @{
   \score @{ @dots{} @}
-  \layout @{ @dots{} @}
+  \paper @{ @dots{} @}
 @}
 \book @{
   \score @{ @dots{} @}
-  \layout @{ @dots{} @}
+  \paper @{ @dots{} @}
 @}
 @end example