feature #648 Update to Symfony 3.3.9 and fix latest changes (yceruto)

This PR was squashed before being merged into the master branch (closes #648).

Discussion
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Update to Symfony 3.3.9 and fix latest changes

The [second commit][1] remove the unnecessary configuration for controllers services fixed in symfony/symfony#24126

The third commit update Symfony Flex deps and update `phpunit.xml.dist` env vars according to symfony/recipes#170 and symfony/flex#148

<details>
<summary>See "composer update" log trace.</summary>

```bash
Installing dependencies (including require-dev) from lock file
Package operations: 1 install, 45 updates, 0 removals
  - Updating composer/ca-bundle (1.0.7 => 1.0.8): Downloading (100%)
  - Updating symfony/doctrine-bridge (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/stopwatch (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/routing (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/http-foundation (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/event-dispatcher (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/debug (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/http-kernel (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/flex (v1.0.17 => v1.0.19): Downloading (100%)
  - Updating symfony/finder (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/filesystem (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/dependency-injection (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/config (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/class-loader (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/cache (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/framework-bundle (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/console (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating doctrine/doctrine-fixtures-bundle (2.3.0 => v2.4.0): Downloading (100%)
  - Updating symfony/asset (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/dom-crawler (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/browser-kit (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/css-selector (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/expression-language (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/inflector (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/property-access (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/options-resolver (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/intl (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/form (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/monolog-bridge (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/security (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/security-bundle (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/swiftmailer-bundle (v3.0.3 => v3.0.4): Downloading (100%)
  - Updating symfony/twig-bridge (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/twig-bundle (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/translation (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/validator (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/yaml (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/process (v3.3.8 => v3.3.9): Loading from cache
  - Installing composer/semver (1.4.2): Downloading (100%)
  - Updating friendsofphp/php-cs-fixer (v2.5.0 => v2.6.0): Downloading (100%)
  - Updating symfony/var-dumper (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/debug-bundle (v3.3.8 => v3.3.9): Loading from cache
  - Updating symfony/dotenv (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/phpunit-bridge (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/web-profiler-bundle (v3.3.8 => v3.3.9): Downloading (100%)
  - Updating symfony/web-server-bundle (v3.3.8 => v3.3.9): Loading from cache
Generating autoload files
```
</details>

  [1]: ba751c7

Commits
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0f15099 Update to Symfony 3.3.9 and fix latest changes

Author: javiereguiluz