Provide full configuration for Arcanist wrapper as user

Summary:
The image provides a bash config and some symbolic links in /root,
this change mirrors them in home directory.

This is a follow-up for 4d419de04afb.

Test Plan: Tested on Dwellers with arc shell

Reviewers: dereckson

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D2347