Added SetupDiOpenDevRegKey(..), SetupDiEnumDeviceInfo(..) and some constants

I added the following items to the Win32 SetupApi
* SetupDiOpenDevRegKey(..) 
* SetupDiEnumDeviceInfo(..) 
* some constants associated with SetupDiOpenDevRegKey(..)
* Tests both methods

The JavaDocs are copied from MSDN, is this a legal problem?

Why does this need to be a member of the test. Just move it into the implementation of each test, easier to read and easier to understand. No sharing needed.