Merge pull request #19 from kgmx/add_css_to_collection_bookmarks/index

Add css to collection_bookmarks#index
Add gem 'pg'
Delete gem 'sqlite3'
Update config/database.yml to use PostgreSQL
Reset datebase
Merge pull request #20 from kgmx/use_PostgreSQL

Use PostgreSQL
Fix spelling
Create simple_form.ja.yml
Edit application.html.haml
Update views/collection
Create _simple_form.css.scss
Update buttons.css.scss for cancel-button
Update css/collection
Update views/item
Update css/item
Merge pull request #21 from kgmx/add_css_to_simple_form

Add css to simple_form
Add css to users/index.html.haml
Add css to users/show.html.haml
Merge pull request #22 from kgmx/add_css_to_users

Add css to users#index / users#show
Add logo to header