writing an incident flogfile tries to use characters not valid in a Windows filename (':')

[davidsarah]

While reporting the incident in #1395 on a Windows platform, the following error occurred:

[Failure instance: Traceback: <type 'exceptions.IOError'>: [Errno 22] invalid mode ('wb') or filename: u'C:\\tahoeclient\\logs\\incidents\\incident-2011-05-05--18:33:34Z-w2qn32q.flog'

The problem (or at least one problem) is that ':' is not valid in a Windows filename. ​This MSDN article documents the Windows filename validity rules.

Presumably we don't have any test of writing an incident flogfile. This may mean that incident reporting has always been broken on Windows (unless the flogfile naming changed?)