Add recipes created by initial composer install

[emodric]

Symfony recomends storing the symfony.lock file in the repo for your projects.

To reduce friction for new installs, this adds the recipes installed by the initial composer install as well as adding symfony.lock to the repo so users don't have to touch .gitignore when they need to store the lock file.

[andrerom]

hmm, but do we want the lock in our repo?

Atm we don't keep locks in product repos, but when making tags we swap this so projects do keep them: https://github.com/ezsystems/ezplatform/blob/master/bin/.ci/make_tag.sh#L86-L87

[andrerom]

Reminds me that we should consider adding .gitattribute for certain things also: https://medium.com/@pablorsk/be-a-git-ninja-the-gitattributes-file-e58c07c9e915

but that goes for more then just master

[emodric]

Hm, that does solve the .gitignore issue, but it still would cause readding the default assets:install command from the recipe if we would merge #437.

Related issue on symfony/recipes: symfony/recipes#631

Also, Sylius does keep symfony.lock in their repo: https://github.com/sylius/sylius