Merge pull request microsoft#4 from jjw24/update_readme_buildinstructions

Update readme VS build instructions

Author: jjw24

README.md

@@ -55,8 +55,15 @@ Contribution
 Build
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-1. Install Visual Studio 2015 and tick all Windows 10 sdk options
-2. Open powershell with admin permission and `Set-ExecutionPolicy Unrestricted -Scope CurrentUser`
+Install Visual Studio 2015/2017/2019
+
+VS 2015:
+  - Tick all Windows 10 sdk options
+
+VS 2017/2019 and later:
+  - Last Windows 10 SDK which [supported](https://github.com/Wox-launcher/Wox/pull/1827#commitcomment-26475392) UwpDesktop is version 10.0.14393.795. It is needed to compile "Programs" Plugin (UWP.cs), you will see the "References" of Plugin.Programs as broken if you use a later SDK version.
+  - This SDK cannot be installed via VS 2019 installer.
+  - Download and install [Windows 10 SDK version 10.0.14393.795](https://go.microsoft.com/fwlink/p/?LinkId=838916).
 
 Documentation
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