Migrate CDI Tools model to SQL(?) DB instead of using Java collections

Right now we are using Java collections (Maps, Sets, Lists) to store model artifacts. It works ok for small projects. For big projects, we will probably face serious problems with performance and memory usage.
Let's investigate what we can do there and what we can benefit of using SQL DB as a storage for big CDI projects.

Here is the list of possible steps for this work:

1. Create a test project or rather a code which will be able to create big test projects. We will use those projects for testing performance/memore usage for different types of storages.
2. Research different DB/persistence frameworks to find options which are best for our goal.
3. Split CDI Tools core into core interfaces/services for the storage and storage implementations.
4. Implement DB storage and test it against our test projects (see step #1)