Linux GSM Just Cause 3 incomplete - need to install game packages (as per steam instructions)

## User Story
I installed the Just Cause3 server as per LinuxGSM instructions, however the server is incomplete.
A sandbox is created in which players can join but there is no playability ie no game mode

As a LinuxGSM enthusuast, I want extra steps to add the packages so that weapons, vehicles and chat and freeroam game mode is included in the game.

## Basic info

* **Distro:** [debian 9]
* **Game:** [just cause 3]
* **Command:** [start]
* **LinuxGSM version:** latest

## Further Information

This is simply rectified by completing the overall server install with adding the necessary packages.
This is in the steam install documentation :

https://steamcommunity.com/sharedfiles/filedetails/?id=1094953641

Downloading the default packages
Without any packages your server will not be of much use, as you won't even have a chat. JC3MP uses packages to provide Gamemodes and other small features to players. A good starting point are the default packages. In Step 2 we will install these and configure your server for the first time.

Browse to the directory where you installed the JC3MP Server in Step 1
Download the current packages from https://dl.nanos.io/packages.zip
Create a new folder in your JC3MP server installation folder called "packages"
Unzip the packages zip into the folder you just created (Note: This is NOT the same folder as the plugins folder)
Your server will now have the default freeroam gamemode and a few more goodies installed

## To Reproduce

Steps to reproduce the behaviour:
1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

## Expected behaviour