Update README.md

Author: Dllieu

README.md

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 # Visual Studio C++ Plugin
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+[![Build status](https://ci.appveyor.com/api/projects/status/xq7g1w19ufbx3htt?svg=true)](https://ci.appveyor.com/project/Dllieu/visualstudiocppextensions)
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 Custom plugins for Visual Studio 2015+:
 - **Generate Filter**
  - Simple Extension which provide the ability to generate C++ project filters to replicate the folder hierarchy of existing underlying sources / headers