Make Release|Win32 configuration compile
Add <SubSystem> tags to VS projects, specifically, test_serial is a console application
Add x64 Platform to VS project
Add VS related ignore files to .gitignore
Fix warning in Win64
Can use the toolsets from Visual Studio 2010, 2012, 2013

The default is v100 (VS2010)
Merge pull request #69 from linquize/vs

Many Visual Studio fixes