Add Groups definition to glossary (#3616)

MitchellCash · fabaff · commit a01c713fd4c1 · 2017-10-14T06:49:16.000+02:00
diff --git a/source/_data/glossary.yml b/source/_data/glossary.yml
@@ -14,4 +14,5 @@
   description: "Often used abbreviation for Home Assistant."
 - topic: Discovery
   description: The automatic setup of zeroconf/mDNS and uPnP devices after they are discovered.
-
+- topic: Groups
+  description: "Groups are a way to organize your entities into a group."
