Attempt to build CDs on Travis

.travis.yml

@@ -20,6 +20,8 @@ addons:
       - git
       - expect
       - gperf
+      - grub-pc-bin
+      - xorriso
 cache:
   - apt
   - directories:

util/build-travis.sh

@@ -33,9 +33,19 @@ fi
 
 . toolchain/activate.sh
 
-make
+make || exit 1
 
 echo "=== Running test suite. ==="
 
-expect util/test-travis.exp
+expect util/test-travis.exp || exit 1
+
+echo "=== Building live CD ==="
+
+git clone . _cdsource || exit 1
+
+cd _cdsource
+
+make cdrom || exit 1
+
+echo "=== Done. ==="