[Testing] Fix phpunit test dir paths
Further tweaks to the PHPUnit configuration description
Fixes after review
Fix the definition of customizing form's global errors.
Added note about customizing errors for different field types.
Minor rewording. Added tip about meaning of `compound` var and expanded
the example code to contain `else` statements.
[Components][Routing] Fix addPrefix() sample code
bug #3622 [Components][Routing] Fix addPrefix() sample code (bicpi)

This PR was merged into the 2.3 branch.

Discussion
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[Components][Routing] Fix addPrefix() sample code

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | -

The sample code used for demonstrating the
[`Symfony\Component\Routing\RouteCollection::addPrefix()`](http://api.symfony.com/2.3/Symfony/Component/Routing/RouteCollection.html#method_addPrefix) method did not match the signature. I've updated the code to show the provided features when adding a nested route collection. + some minor fixes along the way.

Commits
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e095c13 [Components][Routing] Fix addPrefix() sample code
Added documentation for missing ctype extension
Fixed spelling

Fixed spelling.
Updated references to PHP functions

Updated references to PHP functions using syntax suggested by @WouterJ (`:phpfunction:` role).
feature #3601 Added documentation for missing ctype extension (slavafomin)

This PR was submitted for the 2.4 branch but it was merged into the 2.3 branch instead (closes #3601).

Discussion
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Added documentation for missing ctype extension

Commits
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51cfb23 Updated references to PHP functions
bc439ff Fixed spelling
1d03b0e Added documentation for missing ctype extension
bug #3343 [Testing] Fix phpunit test dir paths (bicpi)

This PR was merged into the 2.3 branch.

Discussion
----------

[Testing] Fix phpunit test dir paths

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | -

Maybe there could be further improvements: The paragraph that follows is a bit confusing. It says *...the following configuration adds the tests from the installed third-party bundles* and then the tests from AcmeDemoBundle are included with `<directory>../src/Acme/Bundle/*Bundle/Tests</directory>`. Mh, the AcmeDemoBundle is a 3rd party bundle that resides in `src`? Shouldn't it include a directory from `vendors` instead to demonstrate this? In addition, the AcmeDemoBundle tests are covered by the standard configuration, so there should be no need for an extra configuration.

It continues with *To include other directories in the code coverage..* and then some dirs from the AcmeDemoBundle are excluded which is also covered by the standard configuration.

What do you think, should I make some more updates here?

Commits
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75bd1e5 Fixes after review
d17a20f Further tweaks to the PHPUnit configuration description
61cdfcc [Testing] Fix phpunit test dir paths
fixing doc roles
fix PHP code block
remove the variables section from the radio button and checkbox type
fix table syntax
fix seealso directive name
Applied some changes according to comments.
[Cookbook][Dynamic Form Modification] Add AJAX sample