Handle network bonding

[Frederick888]

Describe the feature request

My machine has got two NICs and I've configured network bonding using balance-alb via systemd.

This causes bottom to show incorrect network speeds as I guess it adds up all traffics through the physical NICs as well as the virtual bond NIC.

$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp2s0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc fq_codel master bond0 state UP mode DEFAULT group default qlen 1000
    link/ether 00:1e:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
3: enp3s0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc fq master bond0 state UP mode DEFAULT group default qlen 1000
    link/ether 00:1e:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff permaddr 00:1e:xx:xx:xx:xx
4: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
    link/ether 00:1e:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff

$ networkctl list
IDX LINK   TYPE     OPERATIONAL SETUP
  1 lo     loopback carrier     unmanaged
  2 enp2s0 ether    enslaved    configured
  3 enp3s0 ether    enslaved    configured
  4 bond0  bond     routable    configured

4 links listed.

Additional context/details

Users can work around this problem using custom configuration after #279 is supported, but still nice if bottom can detect this automatically I think.

[ClementTsang]

Hm, yeah, this is something I guess I didn't consider with my initial implementation.