Import parameters from vendors

Getting parameters automatically not only from app/config/parameters.yml.dist but also from vendors.

Now you can add a file with default configuration in %BUNDLE%/Resources/config/app/parameters.yml.dist and composer with catch for those parameters while first installation like they have been placed in app/config/parameters.yml.dist.

It will improves copying required parameters to app/config/parameters.yml.dist will be unnecessary during installation new bundle.