user can submit a new cat
test modified to check for error messages if a user submits a blank form
user receives an error message if she submits a blank form
test updated to use new syntax
added url index to cats
Merge branch 'master' into create_cat

Conflicts:
	app/controllers/cats_controller.rb
	config/routes.rb
Merge pull request #3 from LaunchAcademy/create_cat

Create cat