Binary to decimal

[Sukriti-m]

Description 📜

I have added the calculator in which the user can enter the binary value and on clicking the button, the user will receive decimal value and vice-versa. Fixes #312

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Checklist ✅

• [x] I follow Contributing Guidelines & Code of conduct of this project.
• [x] I have performed a self-review of my own code or work.
• [x] My changes generates no new warnings.
• [x] I'm GSSOC'22 contributor
• [x] Have you added a working video of your calculator ?

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Screenshots / Gif (Optional) 📸

https://user-images.githubusercontent.com/93239528/169648794-7bd4aa2a-2d55-49b5-9c49-1470b92ac7cd.mp4

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Please review my PR. @vasu-1 @mansi-garg-12

[awesome-bot-app[bot]]

Thanks for opening the pull request @Sukriti-m! I will look into it ASAP! Till then you can improve your code & you can show your love by staring my repos 😋.

[Sukriti-m]

Please add readme file.

I have made the required changes. Please review

[0xvashishth]

The similar one is already there link