Try to run coveralls only in 0.12

.travis.yml

@@ -1,5 +1,6 @@
 language: node_js
-after_success: ./coveralls.sh
+after_success:
+  - test $TRAVIS_NODE_VERSION = '0.12' && npm run coverage && npm install coveralls@2 && npm run coveralls
 node_js:
   - "0.12"
   - "iojs"

coveralls.sh

@@ -1,6 +0,0 @@
-#!/bin/bash
-set -ev
-if [ "${TRAVIS_NODE_VERSION}" = "0.12" ]; then
-    npm coverage
-    npm run coveralls
-fi

package.json

@@ -49,7 +49,6 @@
   "devDependencies": {
     "buffer-equal": "0.0.1",
     "connect": "^3.4.0",
-    "coveralls": "^2.11.3",
     "eslint": "^1.0.0",
     "istanbul": "^0.3.17",
     "phantomjs": "^1.9.17",