Initial commit of Linux Mass Updater script

Script to update multiple xTuple systems (with multiple packages)
The increase in complexity for supporting an optional package list isn't too bad. Something like this should suffice:
```
if [ "${LOCATION: -1}" -eq "/" ] ; then
  LOCATION=`expr "$LOCATION" : "\\(.*\\)/"  # strip trailing /
fi
if [ -f "$LOCATION"/packagelist.txt ] ; then
  PACKAGELIST=`sed -e "s/#.*//" "$LOCATION"/packagelist.txt` # using sed allows for comments in the packagelist
else
  PACKAGELIST=`ls -L "$LOCATION"/*.gz
fi
```