Timestamp sample macro: `strftime` returns UTF-8 string, need to use `to_unicode` here. Fixes #5778.
This also updates the sample plugin to use datetime, like the rest of Trac 0.11 is doing.
Finally, I've noticed that the win32 specific code in format_datetime is only really necessary for Python 2.3 (related to #2971).
Authored by: cboos 2007-10-29
Parent: [r6112]
Child: [r6114]
