Add UPnP support. Feedback is in logs as suggested by skid_au. The checkbox is still there, but mostly for people who would like to opt out (unfortunately, I can not be sure how this feature may behave for some routers - there's a hell of a lot of bad UPnP implementations.) The Visual Studio stuff is a little messy, so I apologize if anything is a bit off. I tested most configurations and it worked. I also tested CMake on Debian Wheezy, Ubuntu Saucy, and Mac OS X Mountain Lion. All seemed to be OK.