Implement AggregationSource

Adds an AggregationSource resource for each satellite config present on
dbus.

Adds the AggregationSource schema which we had previously ignored.

Tested:
Querying an AggregationSource returned the expected information.

curl localhost/redfish/v1/AggregationService/AggregationSources/5B247A
{
  "@odata.id": "/redfish/v1/AggregationService/AggregationSources/5B247A",
  "@odata.type": "#AggregationSource.v1_3_1.AggregationSource",
  "HostName": "http://122.111.11.1:80",
  "Id": "5B247A",
  "Name": "Aggregation source",
  "Password": null,
}

Service Validator passed.  The Service Validator also passed after
removing the satellite config from the system such that
/redfish/v1/AggregationService/AggregationSources returns an empty
Members array.

Signed-off-by: Carson Labrado <clabrado@google.com>
Change-Id: I88b5fbc15f27cddd330ec22a25427fd8b18cf766
diff --git a/scripts/update_schemas.py b/scripts/update_schemas.py
index a27c156..474c268 100755
--- a/scripts/update_schemas.py
+++ b/scripts/update_schemas.py
@@ -28,6 +28,7 @@
     "AccountService",
     "ActionInfo",
     "AggregationService",
+    "AggregationSource",
     "AggregationSourceCollection",
     "Assembly",
     "AttributeRegistry",