Make IndalekoMachineConfig.py "do the right thing" by invoking the platform specific script

[fsgeek]

Right now IndalekoMachineConfig.py just has test code. To make it easier to use this, we should add a single operator here that invokes the correct script for the given platform.

What this means is:

• If there is a pre-data-gathering step required (e.g., to capture privileged data) this script should mention using it if the pre-requisite file doesn't exist.
• If the pre-requisite (if any) is met, this should invoke the correct script, passing in the correct arguments.
• The documentation in the README.md file should be updated.

This is a pretty small task, but it would simplify the UI for folks.

[fsgeek]

README.md description of the issue (and current approach) added in commit 4a01347.

[fsgeek]

There is an initial change for this that I introduced in commit d350acd. There's more to do here.