Cleanup node v0.6 and v0.11 stuff from Travis.

Removing hacks to get v0.6 tests running; specific npm client version + upgrading mocha.
Also v0.12 of node has been released, therefore there's no reason to still keep testing on v0.11.

.travis.yml

@@ -2,16 +2,12 @@ language: node_js
 node_js:
   - 0.8
   - '0.10'
-  - 0.11
   - 0.12
 before_install:
-  - "test $TRAVIS_NODE_VERSION = '0.6' && npm install -g npm@1.3.26 || npm install -g npm"
+  - npm install -g npm
 script:
   - npm test
   - npm run test-browser
-matrix:
-  allow_failures:
-    - node_js: 0.11
 env:
   global:
     - secure: TKDF1BgAR3S1bqFvikN6O3nbcLk20PDkL6QUVS6IkqQNtL1wXK4+2+GKcvJzOjCZg4OnXAFFtF/rfh9bcNlrGtWCG9CFkuGjUM7iONSQJr0kvCn7jris2jGGBupoPkX7MKlxaqrg6bmbp1QgA42/Hu4AlsNPCBiuFjpvL67VSqg=

package.json

@@ -40,7 +40,7 @@
   },
   "devDependencies": {
     "eslint": "^0.20.0",
-    "mocha": "~2.1.0",
+    "mocha": "^2.1.0",
     "zuul": "^2.1.1"
   },
   "spm": {