**What**
- Fixes tsconfig to ensure a declaration file is included in the build.
**Why**
- Ensure tsserver can understand things from medusa-test-utils
- Get rid of "Could not find a declaration file for module" warning in editors.
What:
- Setups the skeleton for pricing module
- Creates service/model/repository for currency model
- Setups types
- Setups DB
- Moved some utils to a common place
RESOLVES CORE-1477
RESOLVES CORE-1476
