Rewrite Linbo Config parse and catch missing entries

[kiarn]

The code in https://github.com/linuxmuster/linuxmuster-webui7/blob/lmn72/usr/lib/linuxmuster-webui/plugins/lmn_linbo_sync/api.py is old and not understable, must be in linuxmuster-tools rewritten and better be integrate in the devices management.

It's also necessary to check the config entries, see

https://ask.linuxmuster.net/t/linbo-synchronisierung-serverfehler/9406/11