Changes to redirect and filename checks

Added the baseurl check for redirect because if you are using your app inside another directory instead of root, '/' fail gracefully.

Flight::route('/', function(){
    echo 'hello world!';
});

Flight::set('flight.base_url','http://localhost/flightmaster/');
Flight::route('/redirect_to_root', function(){
    Flight::redirect('/');
});
Redirect to "http://localhost/"
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The filename checks is because this really happens with Windows Development to Linux host.