[Cpp] Added Tower Of Hanoi program in Cpp

[ShivamYadav-Coding]

Description

In this pull request i have added program for Tower of Hanoi in c++.

Reference Issue number #242

Type of change

Choosing one or more options from the following as per the nature of your Pull request. NOTE: Check boxes using [x]

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Documentation Update

Checklist:

• [x] I have named my files and folder, according to this project's guidelines.
• [x] My code follows the style guidelines of this project.
• [x] My Pull Request has a descriptive title. (not a vague title like Update index.md)
• [x] I have commented on my code, particularly in hard-to-understand areas.
• [x] I have created a helpful and easy to understand README.md, with problem description and my name.
• [x] I have included a requirements.txt file (if external libraries are required.)
• [x] My changes do not produce any warnings.
• [x] I have starred this repository.
• [ ] I have added a working sample/screenshot of the script.
• [x] I have checked for trailing spaces in file names and none have them.
• [x] I have added (your-name)[your-github-profile-link] in CONTRIBUTORS.md

[pratik-choudhari]

@ShivamYadav-Coding Thank you for this. You have been a commendable contributor. This is the last PR I can merge as this is your 2nd PR. You can still continue to improve previous ones or add new questions in issues.

[ShivamYadav-Coding]

Ok, i would like to thank you that you invest your time and start this initiative of introducing student to how github and pull request work thus help them to know how they can contribute to open source. :)

[pratik-choudhari]

@ShivamYadav-Coding Thank you shivam. I really appreciate you for this feedback. You can spread a word about this repo so others too can come and contribute☺