Make sure we can actually read Apache's error logs.

tests/travis/setup/setup_apache.sh

@@ -50,3 +50,7 @@ sudo apt-get -qq -y install exim4 apcupsd nmap
 
 echo 'Restart apache2'
 sudo /etc/init.d/apache2 restart
+
+# Make sure the error logs are readable for us.
+sudo chmod +rx /var/log/apache2
+sudo chmod +r /var/log/apache2/error.log