don't convert type of time vector

[baggepinnen]

Because it fails if T is a type that don't support nextfloat and AbstractFloat. The user now has direct control over t which is more useful.

[JuliaControlBot]

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Plots were compared to references. 8/11 images have changed, see differences below.
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Difference	Reference Image	New Image
❌ 0.048
✔️ 0.0
✔️ 0.001
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✔️ 0.0
❌ 0.043
❌ 0.059
✔️ 0.01

[codecov]

Codecov Report

Merging #697 (76df370) into master (7ba2598) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #697   +/-   ##
=======================================
  Coverage   87.58%   87.58%           
=======================================
  Files          35       35           
  Lines        3601     3601           
=======================================
  Hits         3154     3154           
  Misses        447      447           

Impacted Files	Coverage Δ
src/timeresp.jl	90.75% <100.00%> (ø)

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