Curate dependencies

[csala]

Resolve #152

Remove unused dependencies and put upper bounds to versions to avoid conflicts when major versions are released.

[codecov-io]

Codecov Report

Merging #153 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #153   +/-   ##
=======================================
  Coverage   65.57%   65.57%           
=======================================
  Files          15       15           
  Lines        1763     1763           
=======================================
  Hits         1156     1156           
  Misses        607      607

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