Notification 2.0 API - Allow to filter notifications with multiple types

The Notification 2.0 API allows to filter notifications by type. Only the data that has the exact type specified in the subscription is forwarded - or all data if the type filter is not specified.

It would be convenient to be able to specify multiple types:

• either with an array of strings as typeFilter instead of the single string

• or using a separator within the typeFilter string