save downloaded arff file as artifact

[jbrea]

No description provided.

[codecov-commenter]

Codecov Report

Merging #8 (00bb922) into dev (14c7da5) will increase coverage by 2.38%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev       #8      +/-   ##
==========================================
+ Coverage   31.96%   34.35%   +2.38%     
==========================================
  Files           1        1              
  Lines         122      131       +9     
==========================================
+ Hits           39       45       +6     
- Misses         83       86       +3     

Impacted Files	Coverage Δ
src/data.jl	34.35% <100.00%> (+2.38%)	⬆️

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[jbrea]

I think this is ready to be merged, although the compatibility with v1.0 is a bit ugly...

[ablaom]

This looks great. Many thanks!