Merge #150

150: Fixed some broken URLs r=korken89 a=Matt90o

These links were not up to date.

Co-authored-by: Matt90o <[email protected]>

Author: bors[bot]

src/03-setup/README.md

@@ -109,6 +109,6 @@ LLVM (http://llvm.org/):
 
 Now follow the instructions specific to the OS you are using:
 
-- [Linux](linux.html)
-- [Windows](windows.html)
-- [macOS](macos.html)
+- [Linux](linux.md)
+- [Windows](windows.md)
+- [macOS](macos.md)