No update on limited internet connection

[niccokunzmann]

It might be that we do not have a high bandwidth Internet connection.
Then, we should not execute CoderDojoOS to update.

We can

• Create a dialog to abort updates
• Locate the computer and classify the wifi networks.
  • When connected to network "coderdojo" and there is an "hpi" wifi present, we can assume to have a good internet connection.
  • If we are connected to eduroam/hpi, we can assume to have a good connection
  • If we create some a file (by clicking a desktop icon for updates) we update

We can do this shortly after 40_wait_for_internet_connection.sh
Note that this means: If there is a problem, the CoderDojoOS will never be updated.

• Change order of steps: Update CoderDojoOS if there is an internet connection, before we run this connection algorithm
• create a use-case-file to configure this.

[niccokunzmann]

@tzwenn This could also help with low-bandwidth Internet connection.