Change client advice, based on the control panel

doc/EN/usage.org

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-* Readme
-After the system has installed a README file will be generated which contains any advice on particular apps installed. Ordinarily you won't need to read it though. You can access it with the following commands:
+* Securing your system
+There are a few things you can do to maximise the security of your system.
+** Use ssh keys rather than passwords
 
-#+BEGIN_SRC bash
-ssh username@domainname -p 2222
-editor ~/README
-#+END_SRC
-
-To exit if you're using emacs (which is the default editor, but can be changed to vim) you can either just close the terminal or use *CTRL-x CTRL-c* followed by the *exit* command.
 * Improving ssh security
 To improve ssh security you can generate an ssh key pair on your system and then upload the public key to the Freedombone.
 

src/freedombone-client

     fi
 
     echo ''
-    echo $'Copy the following into a file called /home/username/.ssh/authorized_keys on the Freedombone server'
+    echo $'Go to the Administrator Control Panel, select "Manage Users", '
+    echo $'"Change user ssh public key" then "yes" and paste the following:'
     echo ''
     echo $(cat /home/$CURR_USER/.ssh/id_rsa.pub)
     echo $(cat /home/$CURR_USER/.ssh/id_ed25519.pub)
     echo ''
+    echo $'Then go to "Security Settings", select "Allow ssh login with passwords"'
+    echo $'and set it to "no".'
 }
 
 function configure_monkeysphere {