Development environment

Added an easy to use development environment based on shared_folder in Vagrant. I've updated the Vagrantfile to use a separate VM with the configuration for development, and renamed the old config VM to default, so any previous installation will remain. The documentation is updated accordingly [README.md](https://github.com/dblommesteijn/invenio-scripts/blob/0cfa4804d05e799a027d88fb82f537acd7ced765/README.md).