VS 2013 Support

[Drakonite]

"In addition, we are only including support for Visual Studio 2015 at this time. If you have a need for earlier VS release let us know by submitting feedback in the issues section of github"

Just chiming in as requested... I use VS2013 and am not upgrading to VS2015. I use VS for far more than just NETMF, and have a much more feature rich edition of VS2013 as compared to what VS2015 Community Edition offers, and having both installed has caused major conflicts for me.

VS2015's login requirement is also a major issue; among other problems with it the system I'm currently setting up for this will regularly be unable to connect to the internet.

For now I'll either try to track down an older version of NETMF or build the code for VS2013 myself. I think there are quite a few people not upgrading to VS2015, so maintaining VS2013 support may be worthwhile.