Fix several bugs in build-razor-winpe.ps1

We were not also installing the en-us cabfiles for language localization.
We do now.

We were also not properly iterating over all the images in install.wim
when injecting drivers.  We do so now.
Start reworking windows 2008 to do image-based installation
Update second-stage.ps1 tempalte to pick the right OS image and set the product key.