Changes required to add devise

Added gem devise and done required changes
Added a model User with devise

generated user model using devise
Generated views for users using devise

Created views using command 'rails generate devise:views'
Added devise and created model user

These are files created/modified after adding devise and creating user
model
Added Bootstrap

Added bootstrap.css to App/assets/stylesheets and
bootstrap.js to App/assets/javascripts
Merge pull request #2 from chinmay001vdus/master

Added gem devise and created model user and its views using devise, added bootstrap