Add Enum\Validation Class and removal of data types not allowed

- Create the class Enum\Validation to simulate a Enum behavior. Initially used in the validation of allowed HTTP methods.
- Remove array declaration from Phrases\Services\Router Class, and substitute by Enum\Validation with the values of HTTP\AllowedTypesRequested
- Create Testes for Enum\Validation class.
- Add use of Phrases\HTTP and Phrases\Enum on Router Class.