[travis] Clean up .travis.yml

.travis.yml

@@ -1,25 +1,19 @@
+sudo: false
 language: node_js
 node_js:
+  - "5"
+  - "4"
   - "0.12"
-  - "0.11"
   - "0.10"
-  - "0.9"
   - "0.8"
-  - "iojs-v1.1"
-  - "iojs-v1.0"
 before_install:
-  - "npm install -g npm@1.4.x"
+  - 'if [ "${TRAVIS_NODE_VERSION}" == "0.8" ]; then npm install -g npm@2.14.15; fi'
 script:
   - "npm run test-travis"
 after_script:
-  - "npm install coveralls@2.11.x && cat coverage/lcov.info | coveralls"
+  - "npm install coveralls@2 && cat coverage/lcov.info | coveralls"
 matrix:
   fast_finish: true
-  allow_failures:
-    - node_js: "0.11"
-    - node_js: "0.9"
-    - node_js: "iojs-v1.1"
-    - node_js: "iojs-v1.0"
 notifications:
   irc:
     channels: