* #2450 1. Refactored Layers Architecture to be a Spring boot app. 2. Changed the xml-based configuration to annotation-based. 3. Used spring's constructor injection to pass around needed objects. 4. Implemented deleteAll() methods for the CakeBakingServiceImpl to be used during testing 5. Implemented a CommandLineRunner to run the spring boot app. And others.
* #2450 added the contents of the etc directory and a README.md
* #2450 made corrections in response to the PR tests
* #2450 made corrections in response to requested changes
* #2450 made corrections in response to requested changes
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Co-authored-by: Ilkka Seppälä <iluwatar@users.noreply.github.com>