gcd function will now supports floating point numbers (Updated)

[harsha14gupta]

Do the checklist before submitting the PR:

• [x] Have you read the guidelines mentioned in CONTRIBUTING.md?
• [x] Have you squashed your commits?

Q: What version of Node.js you've used in the project? (e.g. Node v10.11.0) A: v10.15.0

Q: Mention the Issue Number! (e.g. Fixed #8) A: #192