W3C Logger monthly / custom naming

### Is your feature request related to a problem? Please describe.
IIS allowed the W3C logs to be stored on an hourly, daily, weekly or monthly basis.


The `W3CLogger` supports only daily files, while for many smaller applications, having a separate file for each day is unreasonable. I am seeking a way to have only one log file per month.

### Describe the solution you'd like
I suggest the `W3CLoggerOptions` to be extended in one of two ways:
1. Add an option to configure the rollover behaviour, e.g. `Rollover` enum with `Rollover.Monthly` value. This can be extended in the future to support file size or other types of rollover.
2. Allow specifying custom filename pattern. Rather than hardcoding "yyyyMMdd" pattern into the filename, have this to be the default that can be overridden. When users want monthly files, they could set the pattern to "yyyyMM" instead (similarly for hourly etc.)