*   `Default` instance for `SiftCondition` and `EMDOpts`, as a useful
    alternative to `defaultEO` and `defaultSC` for those who prefer it.
*   `Binary` instances for `EMD`, `HHT`, and related data types.  These are
    based on `Binary` instance for `v a`, so the user must bring the orphan
    instance of their choice into scope.  Not sure if this is the best way to
    do this.