moves exported default values to function

[Noroth]

fixes #40
I bumped the version to 3.1.0 and ran the following make commands:

• cover
• fmt
• release

I hope I didn't forget something, otherwise let me know

[codecov-commenter]

Codecov Report

Merging #44 (b6d0474) into master (7096610) will decrease coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #44      +/-   ##
==========================================
- Coverage   98.90%   98.86%   -0.04%     
==========================================
  Files           2        2              
  Lines          91       88       -3     
==========================================
- Hits           90       87       -3     
  Misses          1        1              

Impacted Files	Coverage Δ
retry.go	98.11% <100.00%> (-0.11%)	⬇️

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[JaSei]

Thanks for your PR

[ghost]

Good move, i must say.