user registration and signin

[vigneshsdev]

This PR contains both frontend and backend codes of User Module

Features Covered:

Login and Registration of a user

Acceptance Criteria:

User Registration:

       Scenario 1: User can Register into the system by providing Business Email, Password, and Full Name using SignUp Form.

       Scenario 2: User can also use Sign-up with Google button to register. 
       It will populate the Business Email and Fullname into the form, 
       As this application is not using any mailing service, the user should give a password to register into the system.

User Login:

    Scenario 1: User can log in to the application by filling up Login form with Business Email and Password. 
    The application will validate and authenticate a user if already Registered.

    Scenario 2: User can also use Sign-in with google feature if already registered. 

[vigneshsdev]

1. Folder structure for each modules can be more categorised like

   components (folder)
       xyz (folder)
           ...
           xyz.component.js
           xyz.component.html
           ...
       abc (folder)
           ...
           abc.component.js
           abc.component.html
           ...
   services (folder)
      xyz.service.js
      abc.service.js
   directives (folder)
      ...
   pipes (folder)
      ...

The folder structure has been changed and commited.