Fix typos in comments and docstrings

[ekmecic]

Just a small PR to fix some typos I noticed while browsing the source and documentation. I am not seeking credit for this, it is a very minor fix.

[ghost]

All CLA requirements met.

[codecov-commenter]

Codecov Report

Merging #401 (530270d) into main (84fe356) will not change coverage.
The diff coverage is 25.00%.

@@           Coverage Diff           @@
##             main     #401   +/-   ##
=======================================
  Coverage   51.01%   51.01%           
=======================================
  Files          80       80           
  Lines        7741     7741           
=======================================
  Hits         3949     3949           
  Misses       3792     3792           

Impacted Files	Coverage Δ
src/Data/HumanEye.jl	0.00% <ø> (ø)
src/Examples/repeating_structure_examples.jl	0.00% <ø> (ø)
src/Geometry/AnalyticIntersection.jl	0.00% <0.00%> (ø)
src/Geometry/CSG/CSG.jl	32.10% <ø> (ø)
src/Geometry/CSG/Interval.jl	81.54% <ø> (ø)
src/Geometry/Primitives/AsphericSurface.jl	59.39% <ø> (ø)
src/Geometry/Primitives/Curves/BSpline.jl	66.66% <ø> (ø)
src/Geometry/Primitives/Curves/Bezier.jl	55.88% <ø> (ø)
src/Geometry/Primitives/NonCSG/ConvexPolygon.jl	61.53% <ø> (ø)
src/Geometry/Primitives/Plane.jl	75.00% <ø> (ø)
... and 17 more

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[BrianGun]

@ekmecic Thank you for taking the time to make this PR. Documentation is an important part of every open source project, but especially so for this project which is being used by people who are probably optical engineers first and programmers second. There is still some bug with the CI, which has nothing to do with your PR. As soon as I figure that out I'll commit the PR.