Windows and IE Version numbering update

Added Windows 8, 8.1, 10, IE9 and IE10 version numbering, per Windows SDK header numbering. Also added missing else for version IE7. Comments clarifying other Windows equivalents additionally added.
I wasn't aware that porting API headers was an issue. I'd be curious to find out where the MS license for the headers are, and if they actually cover this case.  Its not really copy-and-paste.  But to answer the previous question, it would be public domain if you hadn't mentioned some Microsoft licensing..