Provide event info for binary manipulation

It would be useful for external caching systems to have additional event information that includes binary uuids / filenames.

Currently a binary field update just triggers a regular node.updated event. There is no information included that the binary field xyz was updated. We could either add the binary uuid/s to the event or provide additional events that cover this aspect (e.g. `binary.updated`, `binary.deleted`, `binary.created`).