Ensure exception gets logged when CustomErrors mode is On

[AroglDarthu]

Related to serilog-web/classic#48

500 errors get logged nicely, but the exception is missing when CustomErrors mode is On.
By using a HandleErrorAttribute the exception can be preserved with a simple call to AddSerilogWebError(exception).

[AroglDarthu]

@tsimbalar I also bumped the versions of the referenced Microsoft and Serilog packages

[tsimbalar]

Thanks a lot for the PR !

Overall, I think the idea is good, but in order to have the minimum impact on consuming apps, I would :

• use IExceptionFilter instead of HandleErrorAttribute (unless I'm missing something obvious)
• only bump the version of SerilogWeb.Classic to v5.0.52, but leave all other dependencies unchanged.

What do you think ?

[AroglDarthu]

Now using IExceptionFilter and reverted all NuGet package updates except SerilogWeb.Classic.

[tsimbalar]

Great, thanks !

This will probably need a bit of testing just to be sure we don't screw it up for some users, as there are many combinations of configuration, with Custom Errors enabled / disabled , as listed in serilog-web/classic#29 ... but I don't think we would break any app with those changes, so LGTM 🚀 !!

Thanks !

[tsimbalar]

This should be available soon :)

https://www.nuget.org/packages/SerilogWeb.Classic.Mvc/2.1.25