renovate-config.json: Add grouping settings.

Change-Id: Ic7de39e67e3ea3de175e21132845975b207f4e89
diff --git a/renovate-config.json b/renovate-config.json
index c199ead..a2d8f76 100644
--- a/renovate-config.json
+++ b/renovate-config.json
@@ -1,6 +1,9 @@
 { "$schema": "https://docs.renovatebot.com/renovate-schema.json"
 , "extends":
   [ "config:base"
+  , "group:allNonMajor"
+  , "group:monorepos"
+  , "group:recommended"
   , ":assignAndReview(benkard)"
   , ":autodetectPinVersions"
   , ":disableDependencyDashboard"