convert to duojs

limitations:
- works only in node 0.11
- needs prototype.bind polyfill for phantomjs
duo travis config
add github token to travis config
use realtive paths to node modules
install duo-test globally
fix for failing travis?
Revert "fix for failing travis?"

This reverts commit fa5601d8ed0354a1ed98f788acfaf0ff4a42bc75.
explicitely call node
remove global duo-test
update install instructions with duo
Merge branch 'duojs'