Change stale link in readme to current ClangSharp repository (#175)

Author: elbuhofantasma

README.md

@@ -1,6 +1,6 @@
 # LLVMSharp
 
-LLVMSharp is a multi-platform .NET Standard library for accessing the LLVM infrastructure. The bindings are auto-generated using [ClangSharp](http://www.clangsharp.org) parsing LLVM-C header files.
+LLVMSharp is a multi-platform .NET Standard library for accessing the LLVM infrastructure. The bindings are auto-generated using [ClangSharp](https://github.com/Microsoft/ClangSharp) parsing LLVM-C header files.
 
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