Use /usr/local/share/{tc2,viperserv} for viperserv accounts

Summary:
Currently, the viperserv accounts uses /var/run/<account>.
On FreeBSD, non socket files in /var/run folders are deleted on boot.

This change switches the folder to a more stable path.

/var/run/<account> folders will so only host pid files.

Thanks @amj for the share folder suggestion.

Fixes T1350.

Test Plan: Run on Ysul.

Reviewers: dereckson

Reviewed By: dereckson

Subscribers: amj

Maniphest Tasks: T1350

Differential Revision: https://devcentral.nasqueron.org/D1369