title: Grunt build fails in travis - "Cannot find any-promise implementation"
body: <p>I'm using travis to test my code. Recently the grunt tasks have started to fail without no change being made to anything involved with grunt. (The new commit which is tested contains just very minor changes in two PHP files.)
  Here is the part of log from travis:</p>
  
  <pre><code>$ grunt build:app
  Running "typings:default" (typings) task
  Warning: Cannot find any-promise implementation nor global.Promise. You must   install polyfill or call require("any-promise/register") with your preferred implementation, e.g. require("any-promise/register")("bluebird") on application load prior to any require("any-promise"). Use --force to continue.
  Aborted due to warnings.
  The command "grunt build:app" exited with 3.
  </code></pre>
  
  <p>I tried to search for that warning message but couldn't find anything useful.</p>
  
  <p>One more thing: When I run <code>grunt build:app</code> locally on my pc it works just fine.</p>
  
  <p>Thanks for your time :)</p>