[hpsdr] VS2013 will not allow building on WinXP

[George Byrkit]

So here's the thing.  VS2013 will NOT install on WinXP.  So if Doug and Joe and I upgrade
from VS2010 (which WILL install on WinXP) to VS2013, you will no longer be able to build
PowerSDR or Kiss Konsole on WinXP.  If that's a pain for too many of you, we won't be able
to move forward.  If it's OK will the vast majority, we would be able to upgrade to VS2013
for development.

Trying to keep it possible for those of you who want to build and experiment with the
source code on as many supported platforms as possible is always one of our goals and
guiding principles.

So how many of you are (still) using WinXP as your development environment for KISS
Konsole (or Gordon's Hera), or PowerSDR?  For many reasons, we recommend using Windows 7
or above, preferring in many cases to use Windows 7 for development at this point.

73
George K9TRV