Ringspy

- change the packaging configurations according to PEP 517
- now RingsPy supports python 3.11 and no longer supports python 3.6
- temporarily fix the hexallatice version to 1.2.1 (as the higher versions might cause the Qt errors)

- update README

- The first stable release is here!
- Modified paper.md for acceptance in JOSS
- If you see any bugs/questions, please email me: haoyin2022 [at] u (dot) northwestern (dot) edu

- Rewrite the logic for the longitudinal generation: now users define "number of segments" instead of "segment length" to achieve a more physical transition in the longitudinal direction. For more details, see https://github.com/openjournals/joss-reviews/issues/4945#issuecomment-1443872940.
- Fix a bug that can cause the wrong 3D rotations for longitudinal connectors (joints) when the theta (twisting angle of the longitudinal extrusion) is large.
- Fix a bug for specifying the clipping box shape in "RebuildVoronoi".

- fix the test for reading existing sites
- minor updates for README

- Add a new radial growth rule: binary_lloyd, which allows the usage of Lloyd's relaxation for a more regular mesh generation
- Add a test for the generation with Lloyd's relaxation
- Rename a few variables in the package to have more generic meanings
- Add explanatory comments for functions in the MeshGenTool.py
- Update the README