Refactor with Generics

[k-yomo]

• Refactored with generics
• Upgrade library version to v2

[codecov]

Codecov Report

Merging #20 (f4ae08e) into master (6c39372) will increase coverage by 10.18%.
The diff coverage is 80.64%.

@@             Coverage Diff             @@
##           master      #20       +/-   ##
===========================================
+ Coverage   78.94%   89.13%   +10.18%     
===========================================
  Files           4        3        -1     
  Lines         190       92       -98     
===========================================
- Hits          150       82       -68     
+ Misses         27        8       -19     
+ Partials       13        2       -11     

Impacted Files	Coverage Δ
example/article.go	100.00% <ø> (ø)
factory.go	90.47% <80.00%> (-9.53%)	⬇️
reflectutil.go	73.33% <100.00%> (-26.67%)	⬇️

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