Bump to 4 toggleGroups, add autoSize option

autoSize implements Issue #6
Fix implementation of 4th toggle group
Bump URMP to 6 toggle groups.
Bump assembly to alpha 0.7
Big v0.7 update

- Remove radius sizing code.
- Replace topNodeOffsetPerSegment/bottom* with MovingNode config nodes
to allow multiple nodes to be affected.
- Remove breakingForce/Torque control from the plugin.
- Gut and redo the autoSize code.
- Update all example parts and add an interstage fairing part.
Refactor MovingSegment and CloningSegment

Change their names, update config files.
Remove obsolete fields, hide

configurationName and numSegments for auto-sized parts.
Rename AutoSize.bottomOffset

Make it endOffset, since it could be used to grow a part upwards.