Add more typeclasses

[zainab-ali]

Adding more typeclasses as referenced in #4

[codecov-io]

Codecov Report

Merging #23 into master will decrease coverage by 2.02%.
The diff coverage is 76.59%.

@@            Coverage Diff             @@
##           master      #23      +/-   ##
==========================================
- Coverage   83.62%   81.59%   -2.03%     
==========================================
  Files           8        8              
  Lines         116      163      +47     
==========================================
+ Hits           97      133      +36     
- Misses         19       30      +11

Impacted Files	Coverage Δ
src/main/scala/libra/quantity.scala	78.78% <76.59%> (-5.43%)	⬇️

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