Suggest /usr/local/include instead of /usr/include, closes #133

README.md

@@ -63,10 +63,10 @@ The code above produces this output ([try it yourself](https://repl.it/@sharkdp/
 
 To make this practical, the `dbg.h` header should be readily available from all kinds of different
 places and in all kinds of environments. The quick & dirty way is to actually copy the header file
-to `/usr/include` or to clone the repository and symlink `dbg.h` to `/usr/include/dbg.h`.
+to `/usr/local/include` or to clone the repository and symlink `dbg.h` to `/usr/local/include/dbg.h`.
 ``` bash
 git clone https://github.com/sharkdp/dbg-macro
-sudo ln -s $(readlink -f dbg-macro/dbg.h) /usr/include/dbg.h
+sudo ln -s $(readlink -f dbg-macro/dbg.h) /usr/local/include/dbg.h
 ```
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 your operating system or package manager.