add mecab-ext gem
describe and add Item#tokens and Item#generate_tokens
generate_tokens on items's create and update
add mongoid_rails_migrations gem
add migration for "add tokens"
add search action and Item.search
fix top search bar
add tag names to tokens
add db:migrate task to deploy tasks
add README entry for mecab
redescribe Item#generate_tokens for adding tags feature
describe HomeController routing
use shared_context for mecab stubbing
describe Item.search
Merge branch 'add-full-text-search'