Add events for requests

[pkly]

Fixes #1963

Things to consider: at this time it's not possible to pass the full request object in the PreRequest event as that object is created and used by the client below. It could be done if the library would change it so that it's in a separate method so we could override it.

The settting of EventDispatcher could also just be done in the constructor at this point.

[XWB]

Things to consider: at this time it's not possible to pass the full request object in the PreRequest event as that object is created and used by the client below. It could be done if the library would change it so that it's in a separate method so we could override it.

I think that's fine for now. Does the PreRequest provides all the information you need for now?

[pkly]

Yes, I already decorated the request method in our application and it works essentially the same, so this should be fine.

[XWB]

Thanks for you hard work 👍