[WIP] Create a basic structure for phrases development

We create a simple basic structure to organize the application, and simple tests to start with development of phrases application.

**Only merge after #9  is merged**
Just linking #11 
I know PHP is a dynamic language and sometimes it is useful using it on our favor; but I think here is not the case.

Fore every response, evaluating the type returned implies on (at least) 2 extra lines of code when always returning the same type would not. An exception may be better suited here.