Doc: Add contributing section to readme

README.org

@@ -9,32 +9,40 @@ Accurate GameBoy emulator.
 
 *** Clone
 
-#+BEGIN_SRC sh
+#+BEGIN_SRC shell-script
 $ git clone https://gitlab.com/riyyi/garbage
 $ cd garbage
 $ git submodule init
 $ git submodule update
 #+END_SRC
 Or
-#+BEGIN_SRC sh
+#+BEGIN_SRC shell-script
 $ git clone --recursive https://gitlab.com/riyyi/garbage
 #+END_SRC
 
 *** Update
 
-#+BEGIN_SRC sh
+#+BEGIN_SRC shell-script
 $ git pull
 $ git submodule update --recursive
 #+END_SRC
 
 ** Build instructions
 
-#+BEGIN_SRC sh
+#+BEGIN_SRC shell-script
 $ mkdir build
 $ cd build
 $ cmake .. && make
 #+END_SRC
 
+** Contributing
+
+Enable 'commit-hooks' to lint your changes before committing them.
+
+#+BEGIN_SRC shell-script
+$ ./vendor/ruc/script/pre-commit.sh install
+#+END_SRC
+
 ** Libraries
 
 - [[https://github.com/riyyi/ruc][ruc]]