changing tangobox from virtualbox to virt-manager format

[PhilLAL]

Hi,
since debian 10 buster, virtualbox is not anymore supported and debian suggest to use virtual machine manager (https://wiki.debian.org/VirtualBox#Debian_10_.22Buster.22).

I have seen several web pages about converting VM and we could probably convert the TangoBox to a format recognized with virt-manager.

I do not have anymore an OS with VirtualBox but I could test an exported tangobox in a format recognized by virt-manager.

[piogor]

@PhilLAL, should this issue go to tangobox repository?

[PhilLAL]

I opened it here because there is a section dedicated to the VM, but I cloned it into this repo I didn't know, thanks for the info Piotr. :)