Terminate travis if build fails

Signed-off-by: Michal Čihař <michal@cihar.com>

.travis.yml

@@ -26,7 +26,7 @@ before_script:
   - ln -s ../codecov.yml .
 script:
   - cmake .. -DCMAKE_C_COMPILER=$CC -DENABLE_COVERAGE=ON -DCMAKE_BUILD_TYPE=Continuous -DONLINE_TESTING=ON $TESTARGS $ARGS
-  - make
+  - make || travis_terminate 1
   - make test
 after_success:
   - make gcov