Generalize script to work in any environment.

[pfaffle]

There are a lot of references to things that would only work for the CAT's Windows environment. We should generalize these as much as possible and allow a script user to pass in parameters and arguments so it can work in varied environments.

For example ...

• Remove references to Normandy; instead let a user pass in a path to a updated BIOS file (or directory tree).
• Instead of using C:\temp, use the $env:temp environment variable.