Pointing dev branch scripts to point to the dev feed.

1. Modified nuget.config
2. Changed all kvm scripts to point to dev feed.
3. Modified readme to reflect the same.
Updating the home repo with the latest KVM scripts
Fixing samples
Merge pull request #147 from aspnet/fixsamples

Fixing samples to use IApplicationBuilder and aspnet50, aspnetcore50
Updated kvm build
Merge pull request #157 from aspnet/dev

Merging