Automatically generate IP-Adress and Hostname

[frb78]

Please implement the old functionality of the Linbo-GUI: When registering a new client, a suitable hostname and IP address should be automatically generated or suggested and the last used hardware class and room should already be filled in. Maybe based on the last entry in the devices.csv. IP address and PC name then simply increased by 1.

[dorianim]

linbo_cmd preregister will be used for this
https://github.com/linuxmuster/linuxmuster-linbo7/blob/86c80a0af700181fcdc86e305462108994a04bbb/linbofs/usr/bin/linbo_cmd#L3329