Add element to create agent deploy ramdisk with proliant utilities for Ironic

Diskimage-builder can build a ramdisk with ironic-python-agent. Ironic python agent supports hardware managers which can be bundled along with the same ramdisk and can be used for various operations one the node like node cleaning tasks, node zapping tasks, etc. The Proliant hardware manager is part of proliantutils python module (https://github.com/stackforge/proliantutils) and it needs some tools like hpssacli, shred, which can be freely downloaded from the internet.

We need a mechanism to bundle these tools into the ironic-python-agent ramdisk.