Now that we have Format feature we need to make it clear that the filtering is done _before_ any formatting of the events happens.

Proposal:
We have new text for Format that looks like (from proposal):
In order to support this broad variety of event delivery requirements, this specification introduces an abstraction called a Delivery Mode and an abstraction called Delivery Format. These concepts are used as extension points, so that event sources and event consumers may freely create new delivery mechanisms that are tailored to their specific requirements. This specification provides a minimal amount of support for delivery mode and format negotiation by allowing an event source to provide a list of supported delivery modes and formats in response to a subscription request specifying a delivery mode or format it does not support.

add to the end:
When the Delivery Format feature is engaged the formatting of the
going events occurs after any filtering. This ensures that regardless
of what type of formatting might occur, the same Filter dialect/expression
can be used to subset the event stream.