Validate section import from json

[carlos-adir]

This issue expands the Issue #7.

jsonschema handles syntax and value types verification, but some verifications jsonschema isn't capable of doing

• Node labels are unique
• Curves are well defined
  • Curve labels are unique
  • knotvector for curves are ordered
  • Control points of curves are refered in node labels
  • Curves are counter-clockwise oriented
• Shapes are well defined
  • All curve labels are refered in curves
  • Areas are positive
  • Each shape is simple or connected shape
• Materials are well defined
• Sections are well defined
  • Subshapes are refered on shapes
  • Submaterials are refered on materials
  • Intersection subshapes is empty

[carlos-adir]

I'm not sure if this should be a responsability of dataio.py or the Section class

[carlos-adir]

If section has functions like from_json or from_dict, it should be responsability of the class to deal if the input is not correct.

Hence, verification if a material is defined should be made my Material class.

But verification if nodes and curves labels are unique can be made by dataio.py

A safe keyword can be added to skip the verification in these functions.

[carlos-adir]

Previous comment resumes.

For now, some verifications are skiped. I think it's better to improve the package considering the input is good, than implementing verifications.