minor symfony#16523 Reorder upgrade doc (umpirsky)

This PR was submitted for the master branch but it was merged into the 2.8 branch instead (closes symfony#16523).

Discussion
----------

Reorder upgrade doc

Just group "The option "`a`" was renamed to "`b`"." together.

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT

Commits
-------

2c65507 Reorder upgrade steps

Author: fabpot

UPGRADE-3.0.md

@@ -124,6 +124,24 @@ UPGRADE FROM 2.x to 3.0
    ));
    ```
 
+ * The option "`virtual`" was renamed to "`inherit_data`".
+
+   Before:
+
+   ```php
+   $builder->add('address', 'form', array(
+       'virtual' => true,
+   ));
+   ```
+
+   After:
+
+   ```php
+   $builder->add('address', 'form', array(
+       'inherit_data' => true,
+   ));
+   ```
+
  * The method `AbstractType::setDefaultOptions(OptionsResolverInterface $resolver)` and
    `AbstractTypeExtension::setDefaultOptions(OptionsResolverInterface $resolver)` have been
    renamed. You should use `AbstractType::configureOptions(OptionsResolver $resolver)` and
@@ -205,24 +223,6 @@ UPGRADE FROM 2.x to 3.0
    });
    ```
 
- * The option "`virtual`" was renamed to "`inherit_data`".
-
-   Before:
-
-   ```php
-   $builder->add('address', 'form', array(
-       'virtual' => true,
-   ));
-   ```
-
-   After:
-
-   ```php
-   $builder->add('address', 'form', array(
-       'inherit_data' => true,
-   ));
-   ```
-
  * The class `VirtualFormAwareIterator` was renamed to `InheritDataAwareIterator`.
 
    Before: