Clean up the timestamp test.

Need to be checking the timezone flag and the UTC offset in it, too.
Add extra timezone test.

Should be able to handle timezones in ISO 8601 format with the offset in
"+HH:MM" format, instead of just UTC "Z" format.
Extra test for timezone.

While we're at it, test a non-UTC offset in plus notation.
Switch timestamp help over to dateutil.

Use dateutil instead of trying to fight against strptime and datetime,
especially when it comes to non-UTC timestamps.
Fix a comment.

I speak English good.
Extra timezone tests.

Make sure it works at the far ends of the scale.
Update requirements.txt.

Add the python-dateutil library, finally.
Add configuration file for pylint.

Configuring pylint and the output.
Adjust the Makefile with a new full report option.