Update README.md

Add the information on how to request access to the Workgroup documents
on Overleaf

README.md

@@ -6,6 +6,12 @@ For more information on installing and using LDMS: https://ovis-hpc.readthedocs.
 
 To join the LDMS Users Group: https://github.com/ovis-hpc/ovis-wiki/wiki/Mailing-Lists
 
+Besides the Users Group, there have been three sub-workgroups: Best Practices,
+Multi-tenancy, and Stream Security. To request access to the discussion
+documents, create an Overleaf account and email Tom Tucker (tom@ogc.us) your
+email address corresponding to your Overleaf account with the subject "LDMS-UG:
+Request access to Workgroup Documents."
+
 OVIS is a modular system for HPC data collection, transport, storage,
 -log message exploration, and visualization as well as analysis.