Lean config file + route caching support

• The config file for new installations will now reside on config/laravalid.php. There's no need for a separate folder for only a file, right? (refs bgultekin#23)
• it's now possible to use ./artisan route:cache to improve your production performance. To do so, you must use the new action option, pointing to a controller action (something like SiteController@getValidation), and run your validation procedures there. Before, route caching was not possible since the default route was a closure.