Test against iojs on Windows
Test against iojs on Windows

iojs ships a more recent version of npm, which causes most build
failures on Windows
node 0.10 - 0.12 are already covered on travis

bradleylandis/testem,paulot/testem,testem/testem,Addepar/testem,testem/testem,Addepar/testem,paulot/testem,fotinakis/testem,fotinakis/testem,Addepar/testem,bradleylandis/testem,testem/testem,johanneswuerbach/testem,bradleylandis/testem,paulot/testem,fotinakis/testem,johanneswuerbach/testem,johanneswuerbach/testem,Addepar/testem