Build IM docs package

Signed-off-by: Mike Marchetti <mmarchetti@sandvine.com>
Change-Id: I612ba00dd2ba6b15cdac88d1c30681168d078693
diff --git a/Makefile b/Makefile
index 26e3843..4faeb5f 100644
--- a/Makefile
+++ b/Makefile
@@ -85,6 +85,8 @@
 package:
 	tox -e build
 	tox -e build3
+	./build-docs.sh
+
 
 pyangbind: pyang
 	git clone https://github.com/alf-tierno/pyangbind