Added phpdoc_seperation fixer

Replaces #845.
Ok, it happens because we're not aligning each annotation grouped with their type, we're aligning all annotations together.

---

just with the align fixer:

before:
```php
    /*
     * @param Foo $foo
     * @return bool
```

after
```php
    /*
     * @param  Foo $foo
     * @return bool
```

---

another example with just that fixer enabled:

```php
    /*
     * @param Foo $foo
     *
     * @return bool
```

now that code won't be changed

---

Do you see why we need that order now?