improve some docstrings

[baggepinnen]

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[JuliaControlBot]

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Difference	Reference Image	New Image
✔️ 0.001
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[baggepinnen]

Test failures fixed by JuliaSIMD/VectorizationBase.jl@d97ff3d

[codecov]

Codecov Report

Merging #660 (fa393aa) into master (45ffb35) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #660   +/-   ##
=======================================
  Coverage   86.59%   86.59%           
=======================================
  Files          31       31           
  Lines        3326     3326           
=======================================
  Hits         2880     2880           
  Misses        446      446           

Impacted Files	Coverage Δ
src/analysis.jl	87.17% <ø> (ø)

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