kvm should allow taking in a feed where it needs to download KRE from

[Praburaj]

Currently kvm scripts hardcode where it will get the KRE packages from. It currently points to the dev myget feed. We need to have ability to point to a feed and download the KRE packages. This is going to be useful as soon as there are multiple feeds / locations where KRE will be available.

Feed can either be a web url or a UNC or a disk path.