With this update, ocaml built good but ocaml-findlib still
segfault

https://firejail.wordpress.com/download-2/release-notes/

- enable vfat
- enable nvme dirver
- enable NLS for filesystems
- enable configfs module

We need to prevent ifup get stuck forever if there are no lease so we
add -b to udhcp opts.

To give users a way to disable this, we patch udhcpc to only respect -b
flag if -n is not given.

helper config for setting up a simple xenbr0 with dnsmasq

add a subpackage with a default lxcbr0 bridge interface with dnsmasq

This makes it very convenient to set up a private network for lxc
containers with a config that works out of the box.

Make it possible to create bridge interfaces for use with lxc and xen