Step1: Create controllers templates, and create controller generator to copy ALL templates to rails app directory
user erb template to generate controllers, enable  --controllers option to specify controllers, make 'scope' argument required
add better help description
enable empty scope when generating a controller
add test for controllers generator
update description message in the controllers generator
print README instruction after running controller generator
add instruction in the README file for controllers generator. This readme will be printed when user invoke devise:install
fix code example shown in README user will see after running generator
comment out all stubs
refactor code, use a constant insead of a class variable
make scope required
move controller generator info from lib/generators/templates/README to README
add *_path_for stubs in all controllers
fix typo: 'new' action should be 'create' action
add before_action hooks for registrations and sessions controllers to enable user to add extra params
change indentation
simplify sanitizer in *_params function
change before_action to before_filter to make it backward compatible to rails 3.2
Merge pull request #3169 from Chun-Yang/master

 Create controller generator for devise (rails generator devise:controllers users -c sessions)