Change directory finding, Add another link path

I changed directory finding to make sure it will find the correct
directories for all linux distroes. For instance in Arch the SteamApps
directory is in STEAMROOT/Steam/SteamApps/ instead of
STEAMROOT/steam/SteamApps. I added another link path because the
required libraries can from from either of these directories. At least
that was the case in my script.