This PR was squashed before being merged into the 4.0.x-dev branch (closes #464).

Discussion
----------

Default FQCN for invokable controllers

This PR implements the [@dunglas's idea](symfony/symfony#21723 (comment)) to make the `service` argument optional for invokable controllers, it allows to omit this argument when using the new convention of using FQN as id.

 **Before:**
```
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;

/**
 * @route(service="AppBundle\Controller\Hello")
 */
class Hello
{
    private $logger;

    public function __construct(LoggerInterface $logger)
    {
        $this->logger = $logger;
    }

    /**
     * @route("/hello/{name}", name="hello")
     */
    public function __invoke($name = 'World')
    {
        $this->logger->info('log entry...');

        return new Response(sprintf('Hello %s!', $name));
    }
}
```

**After:**
```
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;

class Hello
{
    private $logger;

    public function __construct(LoggerInterface $logger)
    {
        $this->logger = $logger;
    }

    /**
     * @route("/hello/{name}", name="hello")
     */
    public function __invoke($name = 'World')
    {
        $this->logger->info('log entry...');

        return new Response(sprintf('Hello %s!', $name));
    }
}
```
**TODO**
- [x] Add Tests
- [x] Fix fabbot.io

Commits
-------

7463c50 Default FQCN for invokable controllers

…controller/class (yceruto)

This PR was merged into the 3.3-dev branch.

Discussion
----------

[Routing][DX] Add full route definition for invokable controller/class

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT
| Doc PR        | _not yet_

Currently the [`@Route`][1] annotation can be set on the class (for global parameters only). This PR allows you to define the full route annotation for _single_ controllers on the class.

Here a common use case of [ADR pattern][3] applied to Symfony:

**Before:**
```
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;

/**
 * @route(service="AppBundle\Controller\Hello")
 */
class Hello
{
    private $logger;

    public function __construct(LoggerInterface $logger)
    {
        $this->logger = $logger;
    }

    /**
     * @route("/hello/{name}", name="hello")
     */
    public function __invoke($name = 'World')
    {
        $this->logger->info('log entry...');

        return new Response(sprintf('Hello %s!', $name));
    }
}
```

**After:**
```
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;

/**
 * @route("/hello/{name}", name="hello", service="AppBundle\Controller\Hello")
 */
class Hello
{
    private $logger;

    public function __construct(LoggerInterface $logger)
    {
        $this->logger = $logger;
    }

    public function __invoke($name = 'World')
    {
        $this->logger->info('log entry...');

        return new Response(sprintf('Hello %s!', $name));
    }
}
```

This feature does not break any behavior before and works under these conditions:
 * The class cannot contain other methods with `@Route` annotation (otherwise, this works as before: used for global parameters).
 *  <del>The class `@Route` must have the `name` option defined (otherwise, the route is ignored).</del> This one is auto-generated if `null`.
 * The class must be invokable: [`__invoke()` method][2] (otherwise, the route is ignored).

Btw, this PR fix the inconsistency with other route definitions (xml, yml) where the `_controller` parameter points to the class name only (i.e. without method).

  [1]: https://github.com/symfony/symfony/tree/master/src/Symfony/Component/Routing/Annotation/Route.php
  [2]: http://php.net/manual/en/language.oop5.magic.php#object.invoke
  [3]: https://github.com/pmjones/adr

Commits
-------

34e360a Add full route definition to invokable class