Added latest argument to kvm install, which will install the latest kvm version (but not set the default)
Added -p (persitant) switch to kvm install, and implemented kvm upgrade as kvm install latest -p
Fixed some small issues when missing alias folder
Fixed install to exit when package is not found in feed
Added latest argument to kvm install for kvm.ps1, which will install the latest kvm version (but not set the default)
Added help text for install -p
Merge pull request #334 from graemechristie/implement-kvm-install-latest

Implement kvm install latest