Update books.

ehuss · ehuss · commit 722d3d8ef067 · 2020-03-31T11:53:48.000-07:00
diff --git a/src/doc/book b/src/doc/book
@@ -1 +1 @@
-Subproject commit 6fb3705e5230311b096d47f7e2c91f9ce24393d0
+Subproject commit c8841f2841a2d26124319ddadd1b6a245f9a1856
diff --git a/src/doc/nomicon b/src/doc/nomicon
@@ -1 +1 @@
-Subproject commit 9f797e65e6bcc79419975b17aff8e21c9adc039f
+Subproject commit 411197b0e77590c967e37e8f6ec681abd359afe8
diff --git a/src/doc/reference b/src/doc/reference
@@ -1 +1 @@
-Subproject commit e2f11fe4d6a5ecb471c70323197da43c70cb96b6
+Subproject commit 89dd146154474559536d5d4049a03831c501deea
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
@@ -1 +1 @@
-Subproject commit cb369ae95ca36b841960182d26f6d5d9b2e3cc18
+Subproject commit edd2a7e687358712608896730c083cb76c7b401a
