Backward compatibility to v0.8.0007 lost.

Hi David,

L]G asked me to look into why this definition stopped working when upgrading to v0.8.0010.

There were two problems to overcome to get it to work as it did before.

Firstly the output of the Explode and Centroid Components has changed, it now includes Null or Empty branches.

Secondly the Equality Component has reverted back to not handling Points.

hope this is useful.