Add tm.sys.hardware

[maufonfa]

I'm working on extending Napalm functionality but using the F5 SDK. I realized that there's no support for this command.
I don't see any another command where I can get the Hardware Version of the F5.

[maufonfa]

The serial number is also in this command.

[jasonrahm]

this has been merged to development branch and will release on next build. Closing issue.