Add apt cleanup to reduce image size

kiosk_skeleton/build.sh

@@ -103,3 +103,7 @@ dpkg --list | grep "ii  chromium " >> /version-info
 echo -n "Linux kernel version: " >> /version-info
 ls /lib/modules/  | sort -r | head -n 1 >> /version-info
 echo >> /version-info
+
+# Clean up apt cache and remove unused packages
+apt-get clean
+apt-get autoremove -y

kiosk_skeleton/var/www/html/index.php

@@ -1,4 +1,5 @@
 <h1>Kioskbrowser</h1>
+<h2>Version: <?php echo exec('git describe --tags --abbrev=0'); ?></h2>
 
 CPU temperature: <br>
 <?php passthru("sudo vcgencmd measure_temp"); ?>