Implement smart recreate behind an experimental CLI flag

Signed-off-by: Aanand Prasad <aanand.prasad@gmail.com>

compose/utils.py

@@ -0,0 +1,9 @@
+import json
+import hashlib
+
+
+def json_hash(obj):
+    dump = json.dumps(obj, sort_keys=True)
+    h = hashlib.sha256()
+    h.update(dump)
+    return h.hexdigest()