Add --skip-listen flag when generating Rails apps

Some specs fail when Rails is using the 'listen' gem, added in
rails/rails@de6ad56.
The --skip-listen flag option was added in
rails/rails@94dbc48.

Author: bquorning

Rakefile

@@ -36,7 +36,7 @@ namespace :generate do
 
       # Rails 4 cannot use a `rails` binstub generated by Bundler
       sh "rm -f #{bindir}/rails"
-      sh "bundle exec rails new ./tmp/example_app --skip-javascript --skip-sprockets --skip-git --skip-test-unit --skip-bundle --template=example_app_generator/generate_app.rb"
+      sh "bundle exec rails new ./tmp/example_app --skip-javascript --skip-sprockets --skip-git --skip-test-unit --skip-listen --skip-bundle --template=example_app_generator/generate_app.rb"
 
       in_example_app do
         sh "./travis_retry_bundle_install.sh 2>&1"
@@ -158,7 +158,7 @@ namespace :no_active_record do
 
         # Rails 4 cannot use a `rails` binstub generated by Bundler
         sh "rm -f #{bindir}/rails"
-        sh "bundle exec rails new #{example_app_dir} --skip-active-record --skip-javascript --skip-sprockets --skip-git --skip-test-unit --skip-bundle --template=example_app_generator/generate_app.rb"
+        sh "bundle exec rails new #{example_app_dir} --skip-active-record --skip-javascript --skip-sprockets --skip-git --skip-test-unit --skip-listen --skip-bundle --template=example_app_generator/generate_app.rb"
 
         in_example_app(:app_dir => example_app_dir) do
           sh "./travis_retry_bundle_install.sh 2>&1"