N°8771 - Add Symfony form component to iTop core (#760)

- Add Symfony Form Component
- Add Symfony CSRF security component
- Add iTop default form template
- Add Twig debug extension to Twig Environment
- Add iTop abstract controller facility to get form builder
- Add Twig filter to make trans an alias of dict_s filter

lib/symfony/password-hasher/README.md

@@ -0,0 +1,40 @@
+PasswordHasher Component
+========================
+
+The PasswordHasher component provides secure password hashing utilities.
+
+Getting Started
+---------------
+
+```
+$ composer require symfony/password-hasher
+```
+
+```php
+use Symfony\Component\PasswordHasher\Hasher\PasswordHasherFactory;
+
+// Configure different password hashers via the factory
+$factory = new PasswordHasherFactory([
+    'common' => ['algorithm' => 'bcrypt'],
+    'memory-hard' => ['algorithm' => 'sodium'],
+]);
+
+// Retrieve the right password hasher by its name
+$passwordHasher = $factory->getPasswordHasher('common');
+
+// Hash a plain password
+$hash = $passwordHasher->hash('plain'); // returns a bcrypt hash
+
+// Verify that a given plain password matches the hash
+$passwordHasher->verify($hash, 'wrong'); // returns false
+$passwordHasher->verify($hash, 'plain'); // returns true (valid)
+```
+
+Resources
+---------
+
+ * [Documentation](https://symfony.com/doc/current/security.html#c-hashing-passwords)
+ * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+ * [Report issues](https://github.com/symfony/symfony/issues) and
+   [send Pull Requests](https://github.com/symfony/symfony/pulls)
+   in the [main Symfony repository](https://github.com/symfony/symfony)