jgvariant-tool: Add example output to the readme file.

Change-Id: Iec0b38e07b4c1529ac3b2b1aa810c58af3486ba6
diff --git a/README.md b/README.md
index caa9938..07558b0 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,39 @@
 
     $ jgvariant ostree summary read ./jgvariant-ostree/src/test/resources/ostree/summary
 
+Output:
+
+    {
+        "entries": [
+            {
+                "ref": "mulkos/1.x/amd64",
+                "value": {
+                    "checksum": "66ff167ff35ce87daac817447a9490a262ee75f095f017716a6eb1a9d9eb3350",
+                    "metadata": {
+                        "fields": {
+                            "ostree.commit.timestamp": 1640537170
+                        }
+                    },
+                    "size": 214
+                }
+            }
+        ],
+        "metadata": {
+            "fields": {
+                "ostree.summary.last-modified": 1640537300,
+                "ostree.summary.tombstone-commits": false,
+                "ostree.static-deltas": {
+                    "3d3b3329dca38871f29aeda1bf5854d76c707fa269759a899d0985c91815fe6f-66ff167ff35ce87daac817447a9490a262ee75f095f017716a6eb1a9d9eb3350": "03738040e28e7662e9c9d2599c530ea974e642c9f87e6c00cbaa39a0cdac8d44",
+                    "31c8835d5c9d2c6687a50091c85142d1b2d853ff416a9fb81b4ee30754510d52": "f481144629474bd88c106e45ac405ebd75b324b0655af1aec14b31786ae1fd61",
+                    "31c8835d5c9d2c6687a50091c85142d1b2d853ff416a9fb81b4ee30754510d52-3d3b3329dca38871f29aeda1bf5854d76c707fa269759a899d0985c91815fe6f": "2c6a07bc1cf4d7ce7d00f82d7d2d6d156fd0e31d476851b46dc2306b181b064a"
+                },
+                "ostree.summary.mode": "bare",
+                "ostree.summary.indexed-deltas": true
+            }
+        }
+    }
+
+
 You can build the tool either as a shaded JAR or as a native executable.
 
 To build and run a shaded JAR: