Models: Use camel case properties and add new properties

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Upgrade to Symfony 2.6 and upgrade other packages

  - Removing twig/twig (v1.16.2)
  - Installing twig/twig (v1.16.3)

  - Removing doctrine/inflector (v1.0)
  - Installing doctrine/inflector (v1.0.1)

  - Removing doctrine/annotations (v1.2.1)
  - Installing doctrine/annotations (v1.2.3)

  - Removing symfony/symfony (v2.5.6)
  - Installing symfony/symfony (v2.6.1)

  - Removing doctrine/dbal (v2.4.3)
  - Installing doctrine/dbal (v2.5.0)

  - Removing doctrine/orm (v2.4.6)
  - Installing doctrine/orm (v2.4.7)

  - Installing doctrine/doctrine-cache-bundle (v1.0.1)

  - Removing doctrine/doctrine-bundle (v1.2.0)
  - Installing doctrine/doctrine-bundle (v1.3.0)

  - Removing swiftmailer/swiftmailer (v5.3.0)
  - Installing swiftmailer/swiftmailer (v5.3.1)

  - Removing symfony/swiftmailer-bundle (v2.3.7)
  - Installing symfony/swiftmailer-bundle (v2.3.8)

  - Removing sensio/distribution-bundle (v3.0.7)
  - Installing sensio/distribution-bundle (v3.0.13)

  - Removing sensio/framework-extra-bundle (v3.0.2)
  - Installing sensio/framework-extra-bundle (v3.0.4)

  - Removing imagine/imagine (v0.6.1)
  - Installing imagine/imagine (0.6.2)

  - Removing liip/imagine-bundle (1.1.0)
  - Installing liip/imagine-bundle (1.2.1)

  - Removing sensio/generator-bundle (v2.4.0)
  - Installing sensio/generator-bundle (v2.5.0)

  - Removing sebastian/environment (1.2.0)
  - Installing sebastian/environment (1.2.1)

  - Removing sebastian/comparator (1.0.1)
  - Installing sebastian/comparator (1.1.0)

  - Removing phpunit/php-code-coverage (2.0.11)
  - Installing phpunit/php-code-coverage (2.0.14)

  - Removing phpunit/phpunit (4.3.4)
  - Installing phpunit/phpunit (4.3.5)

  - Removing kriswallsmith/assetic (v1.2.0)
  - Installing kriswallsmith/assetic (v1.2.1)

  - Removing doctrine/mongodb-odm-bundle (dev-master 1595d14)
  - Installing doctrine/mongodb-odm-bundle (dev-master 9748d11)
    Cloning 9748d11cc73396a74f20c92951425618a3d29fd0

  - Updating friendsofsymfony/user-bundle dev-master (9714a92 => 4ceecb6)
    Checking out 4ceecb62f8bfbee56a5ec83f5ab6124710cf89d1