add devise gem
add devise install generation
add configuration for devise and alert_messages pannels in application page
add devise user model and migrated
add device views and add authenticate_user before_action in application_controller
add book model
add student model
add student_books model for issue books to students
modified student and book model
add students_controller and new action
modified student_controller and views
updated students controller with all crud functions
modified apllication.html.erb for showing login,logout
updated home page
added books controller and modified book model
modified student_book model
add new_books and books_management links in home
add book_management model and controller
update book_managements_controller with available check
updated index pages with home link