Always use absolute paths for includes

It's not safe to assume that the web server will always give you a sane
cwd.

1-front-controller.md

@@ -19,7 +19,7 @@ Inside the `public` folder you can now create your `index.php`. Remember that yo
 ```php
 <?php 
 
-require '../src/Bootstrap.php';
+require __DIR__ . '/../src/Bootstrap.php';
 ```
 
 The `Bootstrap.php` will be the file that wires your application together. We will get to it shortly.

3-error-handler.md

@@ -21,7 +21,7 @@ To install a new package, open up your `composer.json` and add the package to th
 
 Now run `composer update` in your console and it will be installed.
 
-But you can't use it yet. PHP won't know where to find the files for the classes. For this you will need an autoloader, ideally a [PSR-4](http://www.php-fig.org/psr/psr-4/) autoloader. Composer already takes care of this for you, so you only have to add a `require '../vendor/autoload.php';` to your `Bootstrap.php`.
+But you can't use it yet. PHP won't know where to find the files for the classes. For this you will need an autoloader, ideally a [PSR-4](http://www.php-fig.org/psr/psr-4/) autoloader. Composer already takes care of this for you, so you only have to add a `require __DIR__ . '/../vendor/autoload.php';` to your `Bootstrap.php`.
 
 **Important:** Never show any errors in your production environment. A stack trace or even just a simple error message can help someone to gain access to your system. Always show a user friendly error page instead and send an email to yourself, write to a log or something similar. So only you can see the errors in the production environment.
 
@@ -34,7 +34,7 @@ Then after the error handler registration, throw an `Exception` to test if every
 
 namespace Example;
 
-require '../vendor/autoload.php';
+require __DIR__ . '/../vendor/autoload.php';
 
 error_reporting(E_ALL);