add-on uses bower tree so consumers can override ember-data version n…

…aturally ember-cli/ember-cli#1928

lib/ember-addon-main.js

@@ -3,7 +3,9 @@
 module.exports = {
   name: 'ember-data',
   init: function() {
-    this.treePaths.vendor = '../dist';
+    // Using the `bower` tree so that if consumers want to override the
+    // version of ember-data they can simply by normal `bower install` means.
+    this.treePaths.bower = '../dist';
   },
   included: function(app) {
     this.app = app;
@@ -15,12 +17,9 @@ module.exports = {
       }
     };
 
-    // This will use the pre-built version distributed with our package
-    // but still allow consumers to bower install their own version that
-    // will override ours.
     this.app.import({
-      development: 'vendor/ember-data/ember-data.js',
-      production: 'vendor/ember-data/ember-data.prod.js'
+      development: app.bowerDirectory + '/ember-data/ember-data.js',
+      production: app.bowerDirectory + '/ember-data/ember-data.prod.js'
     }, options);
   }
 };