Merge pull request #1 from DNNX/master

Add 'unless' support and fix rake tests
Rework path to the new railtie style. Rework tests. Slightly improves gemspec file
Add model and view helpers to railtie
Include view helpers. Improve tests. Change params[:controller] for more safe controller_name
Clean up code a bit. Add canned gate keeper tests. Safer 404 response.
Rework test class
Replace `render "public/404.html"` with `render file: "public/404.html"`

This change is backward-compatible, so it shouldn't break existing any
existing app.

Previously, calling render "foo/bar" in a controller action was
equivalent to render file: "foo/bar". In Rails 4.2, this has been
changed to mean render template: "foo/bar" instead.

See http://guides.rubyonrails.org/4_2_release_notes.html#render-with-a-string-argument