✨ feat: init the spline module

[aksiome]

Description

This new module adds the following features:

• evaluate: evaluate a curve using 4 control points and a time parameter. (bezier, bspline, catmull_rom, and hermite)
• sample: sample a curve an arbitrary number of control points and a step parameter. (bezier, bspline, catmull_rom, and hermite)
• stream: stream a curve using a callback (bezier, bspline, catmull_rom, and hermite)

Related Issues

closes #241

Additional Notes

see #282 (we may need to change the storage used for the callback)

Tasks to complete before merging

• I agree to release my contribution under the MPL v2 License.
• My pull request is associated with an existing issue.
• I have updated the changelog to reflect my contribution.
• If this pull request adds or modifies a feature:
  • I have documented my changes in the /docs folder.
  • I have thoroughly tested my changes. See testing guidelines.