(CFACT-117) Add Windows networking facts

Adds Windows networking facts, implemented according to facter's behavior.

Major changes were:
- Refactoring the wmi API to return a vector of objects when multiple
  objects are returned, rather than returning those results split into
  ranges of values.
- Returning array values from wmi.
- Added a utility for querying the registry on Windows.
- Require Windows Vista as the minimum OS version.
MinGW defines it to be empty.