travis: limit number of iojs versions

Author: LinusU

.travis.yml

@@ -3,20 +3,7 @@ node_js:
   - "0.8"
   - "0.10"
   - "0.12"
-  - "iojs-v1.0.4"
-  - "iojs-v1.1.0"
-  - "iojs-v1.2.0"
-  - "iojs-v1.3.0"
-  - "iojs-v1.4.3"
-  - "iojs-v1.5.1"
-  - "iojs-v1.6.4"
-  - "iojs-v1.7.1"
   - "iojs-v1.8.4"
-  - "iojs-v2.0.2"
-  - "iojs-v2.1.0"
-  - "iojs-v2.2.1"
-  - "iojs-v2.3.4"
-  - "iojs-v2.4.0"
   - "iojs-v2.5.0"
 before_install:
   - '[ "${TRAVIS_NODE_VERSION}" != "0.8" ] || npm install -g [email protected]'