If dateutil is present, we'll use that. If not, we'll use some regexes from the fixed_datetime module.
Thus, using the XEP-0082 and XEP-0202 introduces a dependency on the dateutil package (installable using pip install python-dateutil). Maybe we'll be able to rework how these plugins work to avoid needing dateutil, but for now this will have to do.
Namely, minutes and seconds were reversed.
This should make things much easier for any stanza that uses timestamps.
