Add .nuspec file

[jrecuerda]

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Description

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Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Commits

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  1. Subject is separated from body by a blank line
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  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
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License

• Add a Mozilla Public License 2.0 license header to all the new files.

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[codecov]

Codecov Report

Merging #7 into master will increase coverage by 19.68%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master       #7       +/-   ##
===========================================
+ Coverage   76.23%   95.91%   +19.68%     
===========================================
  Files          13       13               
  Lines        1321     1321               
  Branches       53       53               
===========================================
+ Hits         1007     1267      +260     
+ Misses        295       39      -256     
+ Partials       19       15        -4

Impacted Files	Coverage Δ
src/KhivaArray.cs	90.64% <0%> (+4.85%)	⬆️
src/Library.cs	100% <0%> (+88.88%)	⬆️
src/LinAlg.cs	100% <0%> (+100%)	⬆️
src/Matrix.cs	100% <0%> (+100%)	⬆️
src/Normalization.cs	100% <0%> (+100%)	⬆️
src/Polynomial.cs	100% <0%> (+100%)	⬆️
src/Statistics.cs	100% <0%> (+100%)	⬆️
src/Regularization.cs	100% <0%> (+100%)	⬆️
src/Regression.cs	100% <0%> (+100%)	⬆️

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[dcuestam]

Nice!