[BL training-materials-updates] Add higher resolution images

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=e7c3ab6724aa866aa24835eba6ed7e4c1eeebfa8

>---------------------------------------------------------------

commit e7c3ab6724aa866aa24835eba6ed7e4c1eeebfa8
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Tue Apr 10 10:28:17 2018 +0200

    Add higher resolution images
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


>---------------------------------------------------------------

e7c3ab6724aa866aa24835eba6ed7e4c1eeebfa8
 slides/sysdev-intro/freebox.jpg                 | Bin 251276 -> 0 bytes
 slides/sysdev-intro/linksys-wireless-router.jpg | Bin 0 -> 137418 bytes
 slides/sysdev-intro/point-of-sale.jpg           | Bin 29551 -> 194898 bytes
 slides/sysdev-intro/sysdev-intro.tex            |  12 ++++++++----
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/slides/sysdev-intro/freebox.jpg b/slides/sysdev-intro/freebox.jpg
deleted file mode 100644
index 4a70c7f..0000000
Binary files a/slides/sysdev-intro/freebox.jpg and /dev/null differ
diff --git a/slides/sysdev-intro/linksys-wireless-router.jpg b/slides/sysdev-intro/linksys-wireless-router.jpg
new file mode 100644
index 0000000..1a4249e
Binary files /dev/null and b/slides/sysdev-intro/linksys-wireless-router.jpg differ
diff --git a/slides/sysdev-intro/point-of-sale.jpg b/slides/sysdev-intro/point-of-sale.jpg
index 80957c6..4a045d9 100644
Binary files a/slides/sysdev-intro/point-of-sale.jpg and b/slides/sysdev-intro/point-of-sale.jpg differ
diff --git a/slides/sysdev-intro/sysdev-intro.tex b/slides/sysdev-intro/sysdev-intro.tex
index 11ba21d..c7e316a 100644
--- a/slides/sysdev-intro/sysdev-intro.tex
+++ b/slides/sysdev-intro/sysdev-intro.tex
@@ -168,24 +168,28 @@
   running Linux}
 
 \begin{frame}
-  \frametitle{Personal routers}
+  \frametitle{Wireless routers}
   \begin{center}
-    \includegraphics[width=0.7\textwidth]{slides/sysdev-intro/freebox.jpg}
+    \includegraphics[width=0.7\textwidth]{slides/sysdev-intro/linksys-wireless-router.jpg}
   \end{center}
+  \tiny
+  Image credits: Evan Amos (\url{https://bit.ly/2JzDIkv})
 \end{frame}
 
 \begin{frame}
 \frametitle{Television}
   \begin{center}
-    \includegraphics[width=0.7\textwidth]{slides/sysdev-intro/television.jpg}
+    \includegraphics[width=0.9\textwidth]{slides/sysdev-intro/television.jpg}
   \end{center}
 \end{frame}
 
 \begin{frame}
 \frametitle{Point of sale terminal}
   \begin{center}
-    \includegraphics[width=0.7\textwidth]{slides/sysdev-intro/point-of-sale.jpg}
+    \includegraphics[width=0.5\textwidth]{slides/sysdev-intro/point-of-sale.jpg}
   \end{center}
+  \tiny
+  Image credits: \url{https://bit.ly/2H8F9YR}
 \end{frame}
 
 \begin{frame}