Ember-cli how to change input path of files

I am new to ember. But for a particular task i need to change input path of templates to compile. i.e default is app/templates. but i want to change this path. I have read the ember-cli-build.js file but i can edit only output path. how can i edit the input path. My ember-cli-build.js

var EmberApp = require('ember-cli/lib/broccoli/ember-app');

module.exports = function(defaults) {
  var app = new EmberApp(defaults, {
    // Add options here
    outputPaths: {
      app: {
        html: 'ember_build_index.html'
      }
    }
  });

  // Use `app.import` to add additional libraries to the generated
  // output files.
  //
  // If you need to use different assets in different
  // environments, specify an object as the first parameter. That
  // object's keys should be the environment name and the values
  // should be the asset to use in that environment.
  //
  // If the library that you are including contains AMD or ES6
  // modules that you would like to import into your application
  // please specify an object with the list of modules as keys
  // along with the exports of each module as its value.

app.import('bower_components/bootstrap/dist/js/bootstrap.min.js');
app.import('bower_components/bootstrap/dist/css/bootstrap.min.css');
app.import('bower_components/bootstrap/dist/css/bootstrap.css.map');
  return app.toTree();
};