Add heapq module docs to the dependency information.
diff --git a/Doc/Makefile.deps b/Doc/Makefile.deps
index 7693c21..ac4205b 100644
--- a/Doc/Makefile.deps
+++ b/Doc/Makefile.deps
@@ -261,6 +261,7 @@
 	lib/libcalendar.tex \
 	lib/libpopen2.tex \
 	lib/libbisect.tex \
+	lib/libheapq.tex \
 	lib/libmimetypes.tex \
 	lib/libsmtplib.tex \
 	lib/libcmd.tex \