Porting python implementation to ruby

[ProGM]

Hi there,

This is a porting of the python implementation in Ruby. I need this library for our company projects in Ruby on Rails 💎

I hope you'll decide to merge this ;)

Implementation details:

• Supports ruby 2.7+
• It's ready to be released on rubygems.org
• Tests use made with rspec, implementing the same suite of Python (runnable via bundle exec rspec)
• Documentation using Yard (runnable via bundle exec yardoc)
• It's configured with rubocop for code linting

[sergykorets]

Please merge

[ProGM]

@roshats Hi, I've made all the requested changes. Let me know if it's all fine or it's ready to be merged :)

[roshats]

Thanks @ProGM .

@VeaaC , I think me can merge this Pull Request and publish ruby gem.

[VeaaC]

@ProGM the commits needs to be signed, then I can go ahead an merge ( https://docs.github.com/en/authentication/managing-commit-signature-verification/about-commit-signature-verification )

[ProGM]

@VeaaC @roshats Commits signed ;)

[VeaaC]

Merging. @roshats / @ProGM can you also add some CI to test against the shared conversion tests in https://github.com/heremaps/flexible-polyline/tree/master/test ?