pass bridge value to vznetcfg script

currently, only ifacenameis passed to vznetcfg script. (and vznetaddbr)

this is ok for vmstart,
but if we want to change veth value online (new bridge, new vlan, new firewall)
or hotplug a new card, with -netif_add

this is not currently possible,
because we read the bridge from vmid.conf in vznetaddbr, but vmid.conf is updated
after -netif_add (and vznetaddbr).
So we never have new value.

This patch pass bridge value as argument to venetcfg script.
We can now compare new and old value in vznetaddr, and see if it's an update or a new tap create.

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
vznetaddbr perl version

this replace the default vznetaddbr script,
using perl code.

This allow to use vlan tag, firewall bridge and openvswitch bridge
like for qemu

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
fwbr bridge cleanup on container umount

call proxmox.umount script, on container umount.
Works if the container is shutdown from vzctl or inside guest with shutdown command

Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
correctly set exec bit for new helper scripts
enable debian hardening-wrapper
fix speeling error
bump version to 4.0-1pve6