BUG: when turning all nodes off via the API, this does not turn off the PSU with the last node.

[jpnadas]

Issue

Whenever the nodes are turned off via the API (either via web interface or tpi), the PSU still remains on. This results in anything (fans, HDDs, etc) powered by it, except for the nodes, to remain active.

Steps to reproduce

1. Plug a fan into the board
2. Power on the nodes (any method)
3. Power off the nodes using the API (either tpi or web interface)
   a. Fan remains on.

Desired solution

The PSU is powered off when nodes are powered off

Workarounds

Turning the nodes off via key1 works as expected (PSU is powered off with the last node).