Keeping up with current Rails HEAD.
Fixed API document page.
Skip CSRF token check for API request.

`api_token` will do insted.
Added API controllers.

API should be separated from HTML controllers.
We should add `.{format}` explicitely.
Added prototype of controller specs.
Added a 100% coveraged spec for api/service.
Added a 100% coveraged specs for api/role.
Added a 100%-covered specs for api/hosts.
Merge pull request #64 from kentaro/api-create-update-destroy

Added API endpoint for creattion and modification.
s/update_attributes/update/ along with Rails 4's way.
Merge branch 'update-deprecated'
Merge branch 'master' of git://github.com/kentaro/triglav into add-serial-id-to-host
add test of serial_id.