Parent add shape

Really useful technique for adding ctrl curves to a null Group.

1. Create your null Grp position, freeze trnsfrms etc, etc.
2. Create your Ctrl Curve and move it into position.
3. Select the curve shape (important to select the shape node by pressing down arrow key)
4. Select Null Grp
5. Type following code:
         parent -s -r

Done! Selet the curve, move it about, it now controls the null group. Select the curve in the hypergraph, delete it - the curve in the viewport is still there, it's connected to the group.