[FEATURE] Event.Kind should be set in logs

[thompson-tomo]

ECS integration/library project(s) (e.g. Elastic.CommonSchema.Serilog): Elastic.CommonSchema.NLog

Is your feature request related to a problem? Please describe. I want to be able to tell by logging at my logs what kind of event i am looking at. The default should be the most common value which is "event"

Describe the solution you'd like I want the event.kind property to be set to event by default

Describe alternatives you've considered Custom layout

Additional context Note I in some cases will be switching to metric, alert and state once #397 is addressed

[thompson-tomo]

@Mpdreamz would u take a pr which implements a layout for each event kind? Note currently I have an open issue (#397) for the difficulty I ran into when trying to set properties.