link to snippets (fix #140)

tex/ch0.tex

@@ -206,7 +206,9 @@ \subsection*{Running examples in the \Coq{} system}
 popular \texttt{Emacs} programming editor (known as \texttt{Proof General})
 and for the \texttt{Visual Studio Code} programming environment
 (known as \texttt{vscoq}).  These extensions and similar projects can easily
-be found by a search on the Internet.
+be found by a search on the Internet. Last, but not least, you can run \Coq{}
+inside a web browser: the code snippets presented in this book can be found
+at \url{https://math-comp.github.io/mcb/snippets/}.
 
 When starting a \Coq{} session, a few commands must be sent to the \Coq{}
 system to tell it to load the \mcbMC{} library and to configure its behavior