Add generictypes extract

[tacianosilva]

Adding extraction of generic types of attributes, methods, and local variables. Relations are created between the entities and the various types present in generics.

This implementation solves the extraction of the code sample in the issue #57.

---

This change is

[tacianosilva]

a discussion (no related file): A tarefa #58 precisa de sua revisão @joaoarthurbm

---

Comments from Reviewable

[tacianosilva]

Reviewed 1 of 12 files at r1. Review status: 1 of 12 files reviewed at latest revision, 1 unresolved discussion.

---

Comments from Reviewable