Part of an akka.actor.IO.Input stream that represents the end of the
This will cause the akka.actor.IO.Iteratee that processes it
to terminate early.
Append another Input to this one.
If 'that' is an akka.actor.IO.EOF then it will replace any
remaining bytes in this Input. If 'this' is an akka.actor.IO.EOF
then it will be replaced by 'that'.