[Mega-Feat] [Create CRUD, full endpoint for Group, add APIdocs, and also add testcases]

[kskarthik05]

1. Create all endpoints for Group

Make a file in routes folder with the name group.js
make a URL as group/create, group/list, group/update, group/delete
then make the required files and functions in services and controller folder.

2. Create all testcases for Group

add testcases for all endpoints of group, inside group.test.js inside of test/routes

3. Create APIDOCs for Group

make api doc in _apidoc.js for all requests in the route for Group

[sumitst05]

Assign this to me