Add resistor color value functions and calculation

[Muhozgu]

Implement functions to get resistor color values and calculate total resistance.

[github-actions]

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[Muhozgu]

Still have to improve some components

[BethanyG]

@Muhozgu - this repo is for exercise content on the Python track of Exercism(dot)org. It is not the place to PR solutions or code for solutions. If you are working on a solution, you need to upload it here. Please only PR to this repo if you have an approved change to the instructional content. Thanks.