Remove the "Releeph" application

Summary:
Ref T9530. Ref T13658. The "Releeph" application was never useful outside of Facebook and any application providing release support would not resemble it much.

It has some product name literal strings, so now is as good a time as any to get rid of it.

This application never left prototype and I'm not aware of any install in the wild that uses it (or has ever used it).

I did not destroy the database itself. I'll issue upgrade guidance and destroy the database in some future release, just in case.

Test Plan: Grepped for "releeph", found no relevant/removable hits.

Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam

Maniphest Tasks: T13658, T9530

Differential Revision: https://secure.phabricator.com/D21792