Complete the requirements of the test

A short description of what i did:
- Encapsulate some logic in small services to avoid fat Controllers and respect SRP
- Used strategy design pattern to implement the different logics for pricing calculation (could have separated the HTML retrieving and parsing from the calculations class, but kept that way due to small amount of time).
- Used basic http authentication for the private API (could done better if had more time, by providing a persistent authentication with tokens on session, something like that)