Ocx

Changed
1. [72 Cardinality of elements and xs:choice](https://github.com/OCXStandard/OCX_Schema/issues/72)

* [73 Remove license boilerplate](https://github.com/OCXStandard/OCX_Schema/issues/73)

Fixed
* [70 Typo in Point3D](https://github.com/OCXStandard/OCX_Schema/issues/70)

FIxed
* [60 Minor schema fixes](https://github.com/OCXStandard/OCX_Schema/issues/60)
Changed
* [63 Cleanup CoordinateSystem](https://github.com/OCXStandard/OCX_Schema/issues/63)
* [64 Cleanup FeatureCope](https://github.com/OCXStandard/OCX_Schema/issues/64)

Removed
* [56 Remove SectionRef from EndCutEnd](https://github.com/OCXStandard/OCX_Schema/issues/56)
* [58 Remove unused substitution groups](https://github.com/OCXStandard/OCX_Schema/issues/58)

Changed
* [49 ReferencePlanes & FrameTable: Revert changes in Issue 36](https://github.com/OCXStandard/OCX_Schema/issues/49)
Removed
* [35 Remove the duplicate trace line definition on the Stiffener and Seam](https://github.com/OCXStandard/OCX_Schema/issues/35)
* [50 Remove WebContour and FlangeContour from the schema](https://github.com/OCXStandard/OCX_Schema/issues/50)
Changed
* [51 LimitedBy BoundingBox: Use the contour start and end points instead](https://github.com/OCXStandard/OCX_Schema/issues/51)