edited Guardfile

(enable to test RSpec under api/v1/)

(enable to run rspec when factory girl file was edited.)
ignore swp file generated by vim
Add organization_controllers_spec and test action index, show and create.

modified organizations_controller to return 404 when no record found for designated id.
remove needless status declaring.
Merge pull request #25 from Mura-Mi/develop-organization

modified behavior when no record found