Some improvements

* Added contributors list to `composer.json` (linked to github contributors graph)
* Improved Behat context
* Fixed/Cleaned/Tested configure options handling
* add `--default` option to `install` command
this looks weird, as it means that releasing from Windows or Linux will have a different behavior.

If the options are different in both platforms, we may need to separate them and use the right ones in the installer, but other places need to be able to use the full metadata of the package