Aphlict notification server to app instances

Summary:
Add Aphlict to app instances so we can have real time notification and real time chat..

Correct ansible role to task

Test Plan:

• Create chat room between two user
• Chat
• Check that the other user see the message without reloading the page

• Create a task
• Assign it to an other user
• Check that the other user sees a notification

Maniphest Tasks: T1245

Differential Revision: https://c4science.ch/D150