Added Visual Studio solution for C test scripts and fixed test bug

- Added a Visual Studio solution that builds the C test scripts on Windows.
 - Updated .gitignore to ignore user specific Visual Studio files
 - Updated .gitignore to ignore Windows build folders
 - Fixed a bug in closeTest. It now properly closes the UDP port a second time after reopening the port to verify that it closed successfully.

.gitignore

@@ -53,3 +53,11 @@ xpcPlugin/Win/xpcPlugin64.lib
 xpcPlugin/Win/xpcPlugin64.exp
 xpcPlugin/xpcPlugin/xpcPlugin/Debug/xplaneConnect.obj
 xpcPlugin/xpcPlugin/xpcPlugin/Debug/xpcPluginTools.obj
+
+*.sdf
+*.opensdf
+*.suo
+xpcPlugin/xpcPlugin/xpcPlugin/Debug
+xpcPlugin/xpcPlugin/xpcPlugin/x64/Debug
+TestScripts/C Tests.win/Debug
+TestScripts/C Tests.win/x64/Debug