added support for C++11 compiler in Travis

Author: scottinet

.travis.yml

@@ -2,6 +2,14 @@ sudo: false
 language: node_js
 node_js:
 - '4.2'
+env:
+- CXX=g++-4.8
+addons:
+  apt:
+    sources:
+      - ubuntu-toolchain-r-test
+    packages:
+      - g++-4.8
 script:
 - grunt && npm test && cat ./coverage/lcov.info | ./node_modules/.bin/codecov
 before_install: npm install -g grunt-cli