Update deps

- Clean Travis config file
  - Only cache deps from composer (avoiding metadata to invalid Travis cache)
  - Update config file to match future version from Travis
  - Remove useless (not so working) `travis_fold`
- Remove `SensioGeneratorBundle` and use `MakerBundle`
  ```
  Package sensio/generator-bundle is abandoned, you should avoid using it. Use symfony/maker-bundle instead.
  ```
- Sort packages in `composer.json`
- Use `laminas/*` package to remove deprecated `zendframework/*` ones:
  ```
  Package zendframework/zend-code is abandoned, you should avoid using it. Use laminas/laminas-code instead.
  Package zendframework/zend-diactoros is abandoned, you should avoid using it. Use laminas/laminas-diactoros instead.
  Package zendframework/zend-eventmanager is abandoned, you should avoid using it. Use laminas/laminas-eventmanager instead.
  ```

app/AppKernel.php

@@ -56,7 +56,7 @@ class AppKernel extends Kernel
             }
 
             if ('dev' === $this->getEnvironment()) {
-                $bundles[] = new Sensio\Bundle\GeneratorBundle\SensioGeneratorBundle();
+                $bundles[] = new Symfony\Bundle\MakerBundle\MakerBundle();
                 $bundles[] = new Symfony\Bundle\WebServerBundle\WebServerBundle();
             }
         }