Badam

1. Migrated the zinger-core from Spring to Ruby on Rails. You can also find the zinger-v1 code changes in an archived repo.
2. Dockerized the zinger-core to make the development and deployment easier.
3. Introduced flexible item modeling along with the support for variants.
4. Redis and ElasticSearch are introduced to improve cache mechanisms and search functionalities.
5. Improved security mechanisms for authentication and authorization.