travis: force build fail on autobahn failure

Signed-off-by: Alexey Galakhov <agalakhov@snapview.de>

.travis.yml

@@ -1,13 +1,15 @@
 language: rust
+rust:
+  - stable
+
+install:
+  - sudo apt-get install python-unittest2
+  - sudo pip install ghp-import urllib3[secure] autobahntestsuite
 
 before_script:
   - export PATH="$PATH:$HOME/.cargo/bin"
 
 script:
   - cargo test --release
-
-after_success:
-  - sudo apt-get install python-unittest2
-  - sudo pip install ghp-import urllib3[secure] autobahntestsuite
   - echo "Running Autobahn TestSuite for client" && ./scripts/autobahn-client.sh
   - echo "Running Autobahn TestSuite for server" && ./scripts/autobahn-server.sh