Internal Server Error (500) when accessing a manifest with no packages

[nathanperkins]

Issue
When an admin accesses a manifest with no packages, they get an internal server error (500), instead of a page.

How to replicate
Attempt to access the "view stable" page on an instance that does not have packages yet. You will receive an internal server error.

I wouldn't consider this a high-priority because the problem goes away once you have packages :)