Revert to using cron for mesh sync

Avoids endless loops

src/freedombone-app-tox

     make uninstall
     rm -rf $INSTALL_DIR/toxid
     sed -i '/tox_avahi/d' $COMPLETION_FILE
-    if [ -f /etc/systemd/system/mesh-sync.service ]; then
-        systemctl stop mesh-sync
-        systemctl disable mesh-sync
-        rm -f /etc/systemd/system/mesh-sync.service
-        systemctl daemon-reload
-    fi
 }
 
 function remove_tox_client {
 
     MESH_SYNC_COMMAND=$rootdir/usr/bin/mesh-sync
     echo '#!/bin/bash' > $MESH_SYNC_COMMAND
-    echo 'while true' >> $MESH_SYNC_COMMAND
-    echo 'do' >> $MESH_SYNC_COMMAND
-    echo '    /usr/local/bin/toxavahi 2> /dev/null' >> $MESH_SYNC_COMMAND
-    echo '    sleep 10' >> $MESH_SYNC_COMMAND
-    echo '    /usr/local/bin/zeronetavahi 2> /dev/null' >> $MESH_SYNC_COMMAND
-    echo '    sleep 10' >> $MESH_SYNC_COMMAND
-    echo 'done' >> $MESH_SYNC_COMMAND
+    echo '/usr/local/bin/toxavahi 2> /dev/null' >> $MESH_SYNC_COMMAND
+    echo '/usr/local/bin/zeronetavahi 2> /dev/null' >> $MESH_SYNC_COMMAND
     chmod +x $MESH_SYNC_COMMAND
 
-    if [ ! -f $rootdir/etc/systemd/system/mesh-sync.service ]; then
-        MESH_SYNC_FILENAME=$rootdir/etc/systemd/system/mesh-sync.service
-        echo '[Unit]' > $MESH_SYNC_FILENAME
-        echo 'Description=mesh-sync - Service publications over avahi' >> $MESH_SYNC_FILENAME
-        echo 'After=network.target' >> $MESH_SYNC_FILENAME
-        echo '' >> $MESH_SYNC_FILENAME
-        echo '[Service]' >> $MESH_SYNC_FILENAME
-        echo 'User=root' >> $MESH_SYNC_FILENAME
-        echo 'ExecStart=/usr/bin/mesh-sync' >> $MESH_SYNC_FILENAME
-        echo 'Restart=on-failure' >> $MESH_SYNC_FILENAME
-        echo 'SuccessExitStatus=3 4' >> $MESH_SYNC_FILENAME
-        echo 'RestartForceExitStatus=3 4' >> $MESH_SYNC_FILENAME
-        echo '' >> $MESH_SYNC_FILENAME
-        echo '[Install]' >> $MESH_SYNC_FILENAME
-        echo 'WantedBy=multi-user.target' >> $MESH_SYNC_FILENAME
-
-        chroot "$rootdir" systemctl enable mesh-sync.service
-    fi
+    cron_add_mins 1 "$MESH_SYNC_COMMAND"
+    cron_add_mins 1 "( sleep 30 ; $MESH_SYNC_COMMAND )"
 }
 
 function mesh_tox_client {