title: Ember build failing
body: <p>I can't build my ember app, I get this error message. Tried </p>
  
  <pre><code>rm -rf node_modules bower_components dist tmp 
  </code></pre>
  
  <p>And installed npm and bower again but it didn't work</p>
  
  <pre><code>The Broccoli Plugin: [SourceMapConcat: Concat: Vendor /assets/vendor.js] failed with:
  Error: ENOENT: no such file or directory, stat '/home/ubuntu/workspace/qr-prototype/configtool-ember/tmp/source_map_concat-input_base_path-DgleBN9U.tmp/0/bower_components/keyboard/dist/js/jquery.keyboard.js'
  at Error (native)
  at Object.fs.statSync (fs.js:844:18)
  at ConcatWithMaps.keyForFile (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/node_modules/broccoli-caching-writer/index.js:90:20)
  at Array.map (native)
  at ConcatWithMaps.CachingWriter._conditionalBuild (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/node_modules/broccoli-caching-writer/index.js:112:65)
  at /home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/node_modules/broccoli-caching-writer/node_modules/broccoli-plugin/read_compat.js:61:34
  at lib$rsvp$$internal$$tryCatch (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/rsvp/dist/rsvp.js:1036:16)
  at lib$rsvp$$internal$$invokeCallback (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/rsvp/dist/rsvp.js:1048:17)
  at lib$rsvp$$internal$$publish (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/rsvp/dist/rsvp.js:1019:11)
  at lib$rsvp$asap$$flush (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/rsvp/dist/rsvp.js:1198:9)
  
  The broccoli plugin was instantiated at: 
  at ConcatWithMaps.Plugin (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/node_modules/broccoli-caching-writer/node_modules/broccoli-plugin/index.js:10:31)
  at ConcatWithMaps.CachingWriter [as constructor] (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/node_modules/broccoli-caching-writer/index.js:21:10)
  at new ConcatWithMaps (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/concat.js:22:17)
  at module.exports (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/node_modules/broccoli-concat/index.js:26:10)
  at EmberApp.concatFiles (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/lib/broccoli/ember-app.js:329:10)
  at EmberApp.javascript (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/lib/broccoli/ember-app.js:1190:12)
  at EmberApp.toArray (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/lib/broccoli/ember-app.js:1542:10)
  at EmberApp.toTree (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/lib/broccoli/ember-app.js:1564:30)
  at module.exports (/home/ubuntu/workspace/qr-prototype/configtool-ember/ember-cli-build.js:35:14)
  at Class.module.exports.Task.extend.setupBroccoliBuilder (/home/ubuntu/workspace/qr-prototype/configtool-ember/node_modules/ember-cli/lib/models/builder.js:55:19)
  </code></pre>