add spec for Item#to_json

To write spec easily, use as_json instead of to_json.
fix String#scrub_html

Because feedzirra(lib/feedzirra/core_ext/string.rb) introduce String#sanitize,
String#scrub_html cannot call ActionView::Helpers::SanitizeHelper#sanitize.
Merge pull request #96 from mzp/fix_relative_date

Fix relative date
fix tiny bug

JSON から新規購読できない
Merge branch 'master' of github.com:fastladder/fastladder
Subscribe not Feed URL on RPC.
fix /user/name for production mode
wrote test.
酷い重複を整理
Merge pull request #98 from mzp/fix_user_page_on_production_mode

fix /user/name for production mode
Merge pull request #97 from ssig33/subscribe_not_feed_on_rpc

Subscribe not Feed URL on RPC.
Move controller initializer
rename common to queue
move by it own role
remove duplicated manage.js
add LDR namespace to API
refactor rate module
add  dom.js to split logic
add flat_menu.js
add mouse_wheel.js