Add more example exceptions that unpickling can raise.

Author: nascheme

Doc/lib/libpickle.tex

@@ -197,7 +197,8 @@ \subsection{Usage}
 This exception is raised when there is a problem unpickling an object,
 such as a security violation.  Note that other exceptions may also be
 raised during unpickling, including (but not necessarily limited to)
-\exception{AttributeError} and \exception{ImportError}.
+\exception{AttributeError}, \exception{EOFError},
+\exception{ImportError}, and \exception{IndexError}.
 \end{excdesc}
 
 The \module{pickle} module also exports two callables\footnote{In the