use rails-assets.org

application.css

/*
  *= require_self
+ *= require bootstrap
  *= require_tree .
  *= require_tree shared
  */
  

application.js

 //= require_self
//= require bootstrap
//= require angular
 //= require_tree .
 //= require_tree shared
 

Gemfile

source 'https://rubygems.org'
# rails-assets.org 追加
source 'https://rails-assets.org'

# gem 'rails-assets-BOWER_PACKAGE_NAME' でassetsを追加

gem 'rails-assets-bootstrap'
gem 'rails-assets-angular'