Updated Book and Reference submodules.

Alexander Regueiro · Alexander Regueiro · commit 4d1802308b12 · 2019-01-16T03:59:06.000Z
diff --git a/src/doc/book b/src/doc/book
@@ -1 +1 @@
-Subproject commit 74d81d80052cb88925f0e73b12fbd0b73ab7b5a0
+Subproject commit 0e9061cbaf95adfb9f3ed36c6cef4c046f282e86
diff --git a/src/doc/reference b/src/doc/reference
@@ -1 +1 @@
-Subproject commit 60077efda319c95a89fe39609803c5433567adbf
+Subproject commit 1c775a1dc5e29bc44b36604b510d6196d98077fa
