Add authentication and authentication workflow

[sonlinux]

• A user needs to first be logged in to access the system features - once logged in they should be redirected to the dashboard page
• A user needs to have an option to log out - once logged out they should be redirected to the login page
• the index view of the system should be set to the dashboard page
• A new user registration action button should be available on the user listing page - and form as a pop up modal
• A new user should be created only by an active staff or superuser for now - we will add more roles for this at a later stage - for this every user can be checked for these statuses by user.is_active, user.is_staff and user.is_superuser respectively
• the register new user action button should only be visible to authenticated above mentioned users only