Posterior Communicating Artery Aneurysm: Giant Aneurysm of the Internal Carotid Artery, Acute SAH, Ruptured Wide Neck Aneurysm, Incorporation of the Fetal Origin of the Posterior Cerebral Artery, Coil Occlusion, Secondary Treatment of the Neck Remnant with a Single Derivo Flow Diverter, Intra-procedural Thrombosis, Intra-arterial Eptifibatide Infusion, Good Clinical Outcome