made cookbook titles more consistent

doc/cookbook/error_handler.rst

-How to convert errors to exceptions
-===================================
+Converting Errors to Exceptions
+===============================
 
 Silex will catch exceptions that are thrown from within a request/response
 cycle. It will however *not* catch PHP errors and notices. You can catch them

doc/cookbook/form_no_csrf.rst

-Disable CSRF Protection on a form using the FormExtension
-=========================================================
+Disabling CSRF Protection on a Form using the FormExtension
+===========================================================
 
 The *FormExtension* provides a service for building form in your application
 with the Symfony2 Form component. By default, the *FormExtension* uses the

doc/cookbook/index.rst

@@ -19,22 +19,22 @@ The cookbook section contains recipes for solving specific problems.
 Recipes
 -------
 
-* :doc:`Accepting a JSON request body <json_request_body>` A common need when
+* :doc:`Accepting a JSON Request Body <json_request_body>` A common need when
   building a restful API is the ability to accept a JSON encoded entity from
   the request body.
 
 * :doc:`Translating Validation Messages<translating_validation_messages>`.
 
-* :doc:`How to use PdoSessionStorage to store sessions in the database
+* :doc:`Using PdoSessionStorage to store Sessions in the Database
   <session_storage>`.
 
-* :doc:`How to disable the CSRF Protection on a form using the FormExtension
+* :doc:`Disabling the CSRF Protection on a Form using the FormExtension
   <form_no_csrf>`.
 
-* :doc:`How to use YAML to configure validation <validator_yaml>`.
+* :doc:`Using YAML to configure Validation <validator_yaml>`.
 
-* :doc:`How to make sub-requests <sub_requests>`.
+* :doc:`Making sub-Requests <sub_requests>`.
 
-* :doc:`How to convert errors to exceptions <error_handler>`.
+* :doc:`Converting Errors to Exceptions <error_handler>`.
 
-* :doc:`How to use multiple monolog loggers <multiple_loggers>`.
+* :doc:`Using multiple Monolog Loggers <multiple_loggers>`.

doc/cookbook/json_request_body.rst

-Accepting a JSON request body
+Accepting a JSON Request Body
 =============================
 
 A common need when building a restful API is the ability to accept a JSON

doc/cookbook/multiple_loggers.rst

-Using multiple monolog loggers
+Using multiple Monolog Loggers
 ==============================
 
 Having separate instances of `Monolog` for different parts of your system is

doc/cookbook/session_storage.rst

-How to use PdoSessionStorage to store sessions in the database
-==============================================================
+Using PdoSessionStorage to store Sessions in the Database
+=========================================================
 
 By default, the :doc:`SessionServiceProvider </providers/session>` writes
 session information in files using Symfony2 NativeFileSessionStorage. Most

doc/cookbook/sub_requests.rst

-How to make sub-requests
-========================
+Making sub-Requests
+===================
 
 Since Silex is based on the ``HttpKernelInterface``, it allows you to simulate
 requests against your application. This means that you can embed a page within

doc/cookbook/validator_yaml.rst

-How to use YAML to configure validation
-=======================================
+Using YAML to configure Validation
+==================================
 
 Simplicity is at the heart of Silex so there is no out of the box solution to
 use YAML files for validation. But this doesn't mean that this is not