TDiary::Application has self routing logic (move from config.ru)
Rack::Builder.app creates the rack app only once
add Static middleware to serve static file
add Application::Configuration class
Merge branch 'master' into routing

Conflicts:
	config.ru
Merge branch 'master' into routing
implement builder interface to add routing and middlewares from plugin
base_dir can not accept an empty path
use autoload to load TDiary::Rack middleware
rename tDiary application extensions
construct self routing via config.builder
implement authenticate interface to change auth middleware
specify the sprokets gem in gemspec
gemspec dependency doesn't load library automatically
require sprokets also in acceptance helper
Merge pull request #315 from tdiary/routing

plugin 機構で config.ru を操作