Bug fix

- The sku attribute is optional. So for the simplicity let's not have
  it.
- When the supportedRuntime element is specified, it trumps what's in
  the executable, so v2.0 needs to be explicitly given.
- Version check is exact check, so "v2.0" and "v2.0.50727" aren't the
  same thing. So we really need to say "v2.0.50727" to let this match
  with .NET 2.0 runtime.