feat(ourlogs): Adjust 'log' protocol per sdk feedback

Now that we've mostly finalized the logs protocol with sdks (see develop doc for more info), we want to update Relay to allow the 'log' item type to be sent in this format.

Also in this PR is some shimming between the updated protocol / event schema and the kafka consumers. This shimming is temporary until the generic EAP items consumers are ready, at which point we'll have to transform the event-schema Relay accepts into the generic eap item kafka.

Author: k-fish