Fix some typos in meter and group REST API

Change-Id: Id32535e154557cba8a4030d9e504c8bd15aa6e9a
diff --git a/web/api/src/main/resources/definitions/Meters.json b/web/api/src/main/resources/definitions/Meters.json
index 0e7488b..46e8727 100644
--- a/web/api/src/main/resources/definitions/Meters.json
+++ b/web/api/src/main/resources/definitions/Meters.json
@@ -5,7 +5,7 @@
     "meters"
   ],
   "properties": {
-    "groups": {
+    "meters": {
       "type": "array",
       "xml": {
         "name": "meters",