[update] documentation

doc/tutorial/tutorial.tex

@@ -159,6 +159,25 @@ $> disassemble 0x20000001
 \end{small}
 
 
+\subsection{libstm32l\_discovery}
+\paragraph{}
+The repository includes the STM32L discovery library source code from ST original firmware packages,
+available here:\\
+\begin{small}
+\begin{lstlisting}[frame=tb]
+http://www.st.com/internet/evalboard/product/250990.jsp#FIRMWARE
+\end{lstlisting}
+\end{small}
+
+\paragraph{}
+It is built using:\\
+\begin{small}
+\begin{lstlisting}[frame=tb]
+$> cd stlink.git/example/libstm32l_discovery/build
+$> make
+\end{lstlisting}
+\end{small}
+
 \newpage
 \section{References}
 \begin{itemize}