gemspec error on creating new rails engine

I am trying to create rails engine using the below link: http://guides.rubyonrails.org/engines.html

I have received below errors

You have one or more invalid gemspecs that need to be fixed. The gemspec at /home/shariq/Documents/plugin/blorgh/blorgh.gemspec is not valid. Please fix this gemspec.

The validation error was '"FIXME" or "TODO" is not a description'

I already tried bundle update and bundle install

Here is all myworking

log

shariq@SDEV-MACHINE:~/Documents/plugin$ ruby -v
ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-linux]
shariq@SDEV-MACHINE:~/Documents/plugin$ rails -v
Rails 5.0.0.1
shariq@SDEV-MACHINE:~/Documents/plugin$ mysql --version
mysql  Ver 14.14 Distrib 5.7.15, for Linux (x86_64) using  EditLine wrapper
shariq@SDEV-MACHINE:~/Documents/plugin$ rails plugin new blorgh --mountable -d mysql
      create  
      create  README.md
      create  Rakefile
      create  blorgh.gemspec
      create  MIT-LICENSE
      create  .gitignore
      create  Gemfile
      create  app
      create  app/controllers/blorgh/application_controller.rb
      create  app/helpers/blorgh/application_helper.rb
      create  app/jobs/blorgh/application_job.rb
      create  app/mailers/blorgh/application_mailer.rb
      create  app/models/blorgh/application_record.rb
      create  app/views/layouts/blorgh/application.html.erb
      create  app/assets/images/blorgh
      create  app/assets/images/blorgh/.keep
      create  config/routes.rb
      create  lib/blorgh.rb
      create  lib/tasks/blorgh_tasks.rake
      create  lib/blorgh/version.rb
      create  lib/blorgh/engine.rb
      create  app/assets/config/blorgh_manifest.js
      create  app/assets/stylesheets/blorgh/application.css
      create  app/assets/javascripts/blorgh/application.js
      create  bin/rails
      create  test/test_helper.rb
      create  test/blorgh_test.rb
      append  Rakefile
      create  test/integration/navigation_test.rb
  vendor_app  test/dummy
         run  bundle install
You have one or more invalid gemspecs that need to be fixed.
The gemspec at /home/shariq/Documents/plugin/blorgh/blorgh.gemspec is not valid. Please fix this gemspec.
The validation error was '"FIXME" or "TODO" is not a description'
shariq@SDEV-MACHINE:~/Documents/plugin$ 

here is gemspec file:

##### log #######
$:.push File.expand_path("../lib", __FILE__)


require "blorgh/version"

Gem::Specification.new do |s|
  s.name        = "blorgh"
  s.version     = Blorgh::VERSION
  s.authors     = ["Shariq"]
  s.email       = ["gr8shariq@live.com"]
  s.homepage    = "TODO"
  s.summary     = "TODO: Summary of Blorgh."
  s.description = "TODO: Description of Blorgh."
  s.license     = "MIT"

  s.files = Dir["{app,config,db,lib}/**/*", "MIT-LICENSE", "Rakefile", "README.md"]

  s.add_dependency "rails", "~> 5.0.0", ">= 5.0.0.1"

end

The error is self-explanatory. You have to replace the "TODO" strings in the gemspec with some "actual" descriptions.