Initial commit
Add "Task".
Apply layout to "application".
add User model, using devise
require authentication
enable username to login
Merge branch 'users' into develop
delete layouts/application.html.erb
add Logout menu
set root on routes
fix: login with username or email
associate Task with User
define sale and product.

Task has some sale items.
And sale item has some products.
define sale and product.
add ignore directory:vendor/bundle/
Merge branch 'feature-material' into develop
fix .gitignore
remove scaffolds.css.scss.
Merge pull request #1 from codeenjin/develop

Merge pull request #1 into Develop
add migrate .rb