The fallback-module will check if the node has connectivity to the
firmware-server. If there is no connectivity in a certain time the
module assumes that the node is no longer part of the mesh.

In this case the wifi is reconfigured to act as a client and to connect
to any open SSID that matches "Freifunk*" and launch the autoupdater.

Thus a node with lost connectivity (e.g. because it is using a different
config, badman-version, etc) can be recovered and flashed with an
update.

Signed-off-by: Chrissi^ <chris@tinyhost.de>