add hhfab switch reinstall and power subcommands

[pau-hedgehog]

Adds switch power|reinstall suboptions to vlab in hhfab.

• vlab switch power enables power management via external PDU servers. For example:

hhfab vlab switch --verbose power --yes --all ON
hhfab vlab switch --verbose power --yes --name leaf-01 CYCLE

A new annotation structure (power:) is supported:

core@control-1 ~ $ kubectl get switch leaf-01 -o=jsonpath='{.metadata.annotations}' | jq
{
  "power.hhfab.githedgehog.com/psu1": "http://192.168.101.10/outlet/1",
}

The pdu credentials are configured in a YAML file in the same folder as fab.yaml with the following structure:

$ cat .pdu.yaml 
pdus:
  192.168.101.10:
    user: user10
    password: password10
  192.168.101.11:
    user: user11
    password: password11

• vlab switch reinstall enables automated NOS reinstall of switches. For example:

hhfab-power vlab switch -v reinstall --yes --all --mode hard-reset
hhfab-power vlab switch -v reinstall --yes --name leaf-01

The default mode (reboot) logs into the switch console, reboots and goes into ONIE NOS install mode to reboot once more and let the switch ready to be managed by the Control node.

The hard-reset mode relies on the power CYCLE operation to cut power briefly for the given switch(es).

Depends On githedgehog/fabric#689

[pau-hedgehog]

After discussing, the default behavior needs to change and reinstall must leave the switches in the ONIE install loop.

This way one can trigger the reinstall and then do the vlab up. Once the control node is ready, the switches will be finally reinstalled.

The initial behavior will be preserved with a flag --wait-ready that will be relayed to the GRUB script.

[pau-hedgehog]

After discussing, the default behavior needs to change and reinstall must leave the switches in the ONIE install loop.

This way one can trigger the reinstall and then do the vlab up. Once the control node is ready, the switches will be finally reinstalled.

The initial behavior will be preserved with a flag --wait-ready that will be relayed to the GRUB script.

I tried this but hhfab requires vlab up:

ubuntu@env-1:~/hhfab$ ./hhfab-pow-reinst vlab switch reinstall --all --yes 
07:37:04 INF Hedgehog Fabricator version=v0.32.1-21-gec342fd8-dirty-a72344
Enter username: admin
Enter password: 
07:37:10 INF Wiring hydrated successfully mode=if-not-present
07:37:10 ERR reinstall failed: preparing VLAB: VLAB directory does not exist: "/home/ubuntu/hhfab/vlab"

Shall we go with the original approach, @Frostman ?