added chat webapp

[Pranav2112]

Description

Added a web app using react js and firebase, in which two people can chat at a time.

Issue

Fixes #9

Type of change

• [x] New Project

Checklist:

• [x] I have included a REAME file for my Project (not for Bug fix)
• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have followed the Contributing Guidelines

[prodigyinfotech]

Fix the README file. DO not use the default README file.