Provide Nasqueron FreeBSD packages catalogue

Summary:
FreeBSD packages are available at https://packages.nasqueron.org/freebsd/
since 75947e1f2a07af5d8.

This change allows each FreeBSD server to acess it.

Test Plan: pkg search salt-tower

Reviewers: dereckson

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D2868