Git ignore and Resharper Sponsor

Author: matthunt-goco

.gitignore

@@ -5,4 +5,4 @@ lib/*
 
 #OSX
 .DS_Store
-/.vs
+/.vs/*

README.md

@@ -39,3 +39,9 @@ Highly welcome! Just fork away and send a pull request. We try and review most p
 
 ## Thanks
 This library would be NOTHING without its [contributors](https://github.com/GeoJSON-Net/GeoJSON.Net/graphs/contributors) - thanks so much!!
+
+## Sponsors
+
+ We have the awesome .NET tools from [JetBrains](http://www.jetbrains.com/).
+
+[![Resharper](http://www.filehelpers.net/images/tools_resharper.gif)](http://www.jetbrains.com/resharper/)