Better error handling

Now that we cull 30 minutes of errors, we can try resending all data.
Previously, we suspected non 204 response codes meant data TSDB didn't know
how to insert (something badly formatted), so we dropped it. The new TSAF
connection timeouts, though, can also return non 204 errors. Thus, retry
everything. Evern if it was bad data and will always fail, it'll get
removed at the 30 minute mark.