Updated 'AppVeyor' project url

It's now linked to the newly created organization project

Author: MrPointer

README.md

@@ -1,6 +1,6 @@
 # Arduino-CMake NG
 
-[![AppVeyor Build](https://ci.appveyor.com/api/projects/status/github/arduino-cmake/Arduino-CMake-NG?svg=true&passingText=Windows%20-%20Passing&failingText=Windows%20-%20Failing&pendingText=Windows%20-%20Pending)](https://ci.appveyor.com/project/arduino-cmake-ng/arduino-cmake-ng)
+[![AppVeyor Build](https://ci.appveyor.com/api/projects/status/github/arduino-cmake/Arduino-CMake-NG?svg=true&passingText=Windows%20-%20Passing&failingText=Windows%20-%20Failing&pendingText=Windows%20-%20Pending)](https://ci.appveyor.com/project/arduino-cmake/arduino-cmake-ng)
 
 **Arduino-CMake** is a framework which allows developers to write Arduino-based programs using any tool that supports cmake. *Arduino-based*? There are many other frameworks out there built upon Arduino's base, such as ESP32, and **we support that**.
 In other words, developers can use their favorite IDEs or text editors on their favorite OS to develop Arduino programs!
@@ -109,4 +109,4 @@ The project has strict contributing guidelines which can be found in the [Contri
 
 ## License
 
-MIT © 2018 [Arduino-CMake](https://github.com/arduino-cmake/arduino-cmake/blob/docs/LICENSE.md)
+MIT © 2018 [Arduino-CMake](https://github.com/arduino-cmake/arduino-cmake/blob/docs/LICENSE.md)