Remove code to handle metadata; instead, let tasks handle metadata and simply concat and send any service.meta.* files/values. Prefix run files with a ts to allow for concurrent runs of the same service.

t/pt-agent/samples/query-history/data001.send

@@ -5,6 +5,10 @@ Content-Disposition: form-data; name="agent"
    "hostname" : "prod1",
    "uuid" : "123"
 }
+--Ym91bmRhcnk
+Content-Disposition: form-data; name="meta"
+
+
 --Ym91bmRhcnk
 Content-Disposition: form-data; name="data"