fix: crypto replaced by crypto-js

[Darapsas]

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Fixes #647 🦕

[Darapsas]

I hope you will approve this one because that rn-nodeify workaround/hack (that I tried earlier) is really ugly and uninspiring. This fix should allow other people to use this package with web/mobile applications with no major changes to their codebases.

[codecov]

Codecov Report

Merging #676 (9b9ca91) into master (5a8470c) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #676   +/-   ##
=======================================
  Coverage   99.61%   99.61%           
=======================================
  Files          22       22           
  Lines         783      783           
  Branches      127      127           
=======================================
  Hits          780      780           
  Misses          3        3           

Impacted Files	Coverage Δ
src/serialize.ts	100.00% <100.00%> (ø)

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[jpoehnelt]

Thank you!