Make date parsing more robust in EODSDriver
Make date parsing more robust in EODSDriver

Sometimes the date stored in metadata.xml wasn't of the same format expected by the strptime calls,
for example, simply a date instead of a date/time.

This change uses dateutil.parser to automatically determine the date format and parse it.

jeremyh/eo-datasets,GeoscienceAustralia/eo-datasets,GeoscienceAustralia/eo-datasets,jeremyh/eo-datasets