add link to ELF diagram

Author: Vladimir Kotal

proc.tex

@@ -770,6 +770,8 @@
 \item Sections contain code, data, symbol table, relocation data, etc.
 \item The \emph{section header table} contains information for the linker, see
 ``\texttt{elfdump -c}'' or ``\texttt{readelf~-S}''.
+\item Nice diagram of ELF internals:
+\url{https://raw.githubusercontent.com/corkami/pics/master/binary/ELF101.png}
 \item Some systems stuck on a format based on the original \emph{a.out} for a
 long time.  For example, OpenBSD moved from \emph{a.out} to ELF in 2003 when
 releasing version 3.4.