The enumerable protocol is once again traversable.
Adds an enumerable protocol with -enumeration.
Consuming a batch’s current object clears it.
Adds an RXEnumerator class.

This class implements -nextObject in terms of the RXEnumerator
primitives, but does not itself conform to RXEnumerator.
Dot notation.
RXFastEnumerator is a much better name.
RXFastEnumerator conforms to RXEnumerator.
RXEnumerator takes emptiness into account during fast enumeration.
Filtering is done with an enumerator.
Replace -isEmpty with -hasNextObject.