create_plug_in_save_dir doc correction

Change-Id: I14350e5fd54a87fe5ea81b40713758867f1a92c5
Signed-off-by: Michael Walsh <micwalsh@us.ibm.com>
diff --git a/lib/gen_plug_in_utils.py b/lib/gen_plug_in_utils.py
index 1d0c78e..fa08866 100755
--- a/lib/gen_plug_in_utils.py
+++ b/lib/gen_plug_in_utils.py
@@ -398,8 +398,10 @@
 
 def create_plug_in_save_dir(plug_in_package_name=None):
     r"""
-    Create a directory suitable for saving plug-in processing data.  See
-    compose_plug_in_save_dir_path for details.
+    Create a directory suitable for saving plug-in processing data and return
+    its path name.
+
+    See compose_plug_in_save_dir_path for details.
 
     Description of argument(s):
     plug_in_package_name            See compose_plug_in_save_dir_path for