Update debugbar.php

as of Laravel 5.5 fire() must be renamed to handle() (barryvdh#705)

https://laravel.com/docs/5.5/upgrade

Artisan
The fire Method

Any fire methods present on your Artisan commands should be renamed to handle

Add note about package discovery

Remove package detection on 2.x

Catch resolving guards

Change case-name of class (allows composer optimizing) (barryvdh#657)

* Change case-name of class (allows composer optimizing)

* rename again :)

Don't inject in 'false' content (eg. streamed etc)

Bump to 2.4

Merge pull request barryvdh#609 from tomvo/1.8

Use Illuminate response

Merge pull request barryvdh#591 from kamui545/fix-route-middlewares

Fix route middlewares list