Reduce memory usage

Up until recently, we were running at 2 second queue time regardless
because of a merging bug.  So 2 seconds is fine.  We are now running
out of memory on the pi's trying to map everything.

Change-Id: Ibe96a00c89b4fff7b88fb52e12ee4b79f5fad5cf
diff --git a/y2020/y2020.json b/y2020/y2020.json
index 808a796..59f3fc0 100644
--- a/y2020/y2020.json
+++ b/y2020/y2020.json
@@ -1,5 +1,5 @@
 {
-  "channel_storage_duration": 5000000000,
+  "channel_storage_duration": 2000000000,
   "maps": [
     {
       "match": {