Wmi class names invalid for golint

[Moe-Kite]

Hi,

First, thanks a lot for this library, it's pretty useful to access easily data through wmi query.

We have one issue with some wmi class (Win32_Fan in our case, but basically most of class) as the class name is invalid for golint as it contains an underscore. That's a blocker as CreateQuery use the type name to build the query.
This PR : #24 gives a solution to that, would it be possible to merge it?

Cheers,
Moe