Merge pull request #75 from Aigeruth/coveralls

Add coveralls.io

.travis.yml

   - npm install -g less
 install:
   - "make"
+  - pip install coveralls
 script:
   - "make tests"
   - "make robot"
   - "make styles"
+  - make coverage
+after_success:
+  coveralls
 notifications:
   irc:
     channels: