[dist] Update .travis.yml to be more modern.

.travis.yml

@@ -1,13 +1,22 @@
+sudo: false
 language: node_js
 node_js:
   - "0.10"
   - "0.12"
-  - "iojs"
+  - "4.1"
+
+before_install:
+  - travis_retry npm install -g npm@2.14.5
+  - travis_retry npm install
+
+script:
+  - npm test
+
+matrix:
+  allow_failures:
+    - node_js: "4.1"
 
 notifications:
   email:
     - travis@nodejitsu.com
   irc: "irc.freenode.org#nodejitsu"
-
-script:
-  npm test