Allow changing of ResolvedFormTypeFactory

Added a new service for the ResolvedTypeFactory. The service name is based on the symfony service name.
Allow strings for levels in the monolog service provider

The monolog service provider requires a constant on Monolog\Logger to be
referenced, which has an integer value. This is not very practical when
working with external configuration files.

This patch accepts strings like debug, info, error, etc. that are
translated to the corresponding logger constant values.

This is an alternative to #882.
Backport static:: to classname:: for PHP 5.3 compatibility
feature #885 Allow strings for levels in the monolog service provider (igorw)

This PR was merged into the 1.2.x-dev branch.

Discussion
----------

Allow strings for levels in the monolog service provider

The monolog service provider requires a constant on Monolog\Logger to be
referenced, which has an integer value. This is not very practical when
working with external configuration files.

This patch accepts strings like debug, info, error, etc. that are
translated to the corresponding logger constant values.

This is an alternative to #882.

Commits
-------

6c97e67 Fix JSON syntax error in monolog provider docs
a7cba30 Reword the documentation on string logger levels
2ef826c Backport static:: to classname:: for PHP 5.3 compatibility
121f3f2 Allow strings for levels in the monolog service provider
Made event callables injectable with pimple. refs #870
fixed CS
feature #894 Replaceable event listener callable (dazz)

This PR was merged into the 1.2.x-dev branch.

Discussion
----------

Replaceable event listener callable

Made event callables injectable with pimple. refs #870

Commits
-------

6690ff5 Made event callables injectable with pimple. refs #870
The form csrf extension should use the translator if available

Fixes #896
Replace Monolog middlewares by an event listener
allow to add object initializers, for complex valdations as unique entity
feature #895 Replace Monolog middlewares by an event listener (GromNaN)

This PR was merged into the 1.2.x-dev branch.

Discussion
----------

Replace Monolog middlewares by an event listener

This is an alternative to the changes introduced by #894 in order to allow replacement of the logging middlewares.
Instead of having a Closure for each listener, this PR introduces a listener class.
The listener can be used independently from the MonologServiceProvider.

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #870
| License       | MIT
| Doc          | yes

Commits
-------

499a626 Replace Monolog middlewares by an event listener
Merge branch 'master' into 2.0-experimental

* master: (39 commits)
  Fix typos
  [doc] Move class definition to the correct section
  prepared the 1.2.0 release
  Fix #856: Revert a064487 as it introduced a BC break
  added PHP 5.6 and HHVM to the Travis file
  fixed CS
  fixed wrong merge
  allow to add object initializers, for complex valdations as unique entity
  Added a note about how to send emails with console commands
  Added contribution instructions
  Added a:b notation warning
  added missing () when creating an object
  Update twig.rst SymfonyBridgesServiceProvider
  Add the Symfony CSSSelector dependency to match the example usage
  Typo in comment, LATE_EVENT is -512 not 512
  Replace Monolog middlewares by an event listener
  The form csrf extension should use the translator if available
  Provides support for the PATCH method for HTTP
  updated docs for previous merge
  fixed CS
  ...

Conflicts:
	composer.json
	doc/changelog.rst
	src/Silex/Application.php
	src/Silex/Provider/FormServiceProvider.php
	src/Silex/Provider/MonologServiceProvider.php
	src/Silex/Provider/ValidatorServiceProvider.php
	tests/Silex/Tests/Provider/MonologServiceProviderTest.php