Added user statistics

Application now supports new endpoint for users statistics - BMI, Ideal weight & Fluid intake calculations.

Users, Activities, Goals APIs

• Application now has REST API endpoints for Users, Activities & Goals.
• Also all endpoints are protected using Basic Auth with roles ADMIN / TESTER / USER / ANYONE.

Supports User CRUD operations and OpenAPI documentation

• User CRUD operations using Postgres SQL database
• Self documenting code using OpenAPI 3.0 and Swagger

User endpoints

Base structure for the application and provide user endpoints.

Full Changelog: https://github.com/matul3jan/healthtrackerrest/commits/V1.0