try to make the generator_spec pass in travis

.travis.yml

@@ -1,26 +1,26 @@
 language: ruby
 rvm:
-  - 1.9.3
+#  - 1.9.3
   - 2.1.2
-  - rbx-2
-  - jruby-19mode
+#  - rbx-2
+#  - jruby-19mode
 #  - ruby-head
 #  - rbx-head
 #  - jruby-head
 
 gemfile:
-  - gemfiles/activerecord_3.2.gemfile
-  - gemfiles/activerecord_4.0.gemfile
+#  - gemfiles/activerecord_3.2.gemfile
+#  - gemfiles/activerecord_4.0.gemfile
   - gemfiles/activerecord_4.1.gemfile
-  - gemfiles/activerecord_edge.gemfile
+#  - gemfiles/activerecord_edge.gemfile
 
 env:
-  - DB=sqlite
+#  - DB=sqlite
   - DB=mysql
-  - DB=postgresql
+#  - DB=postgresql
 
-addons:
-  postgresql: "9.3"
+#addons:
+#  postgresql: "9.3"
 
 script: WITH_ADVISORY_LOCK_PREFIX=$TRAVIS_JOB_ID bundle exec rake --trace all_spec_flavors
 

spec/generator_spec.rb

@@ -9,7 +9,7 @@
 
 RSpec.describe ClosureTree::Generators::MigrationGenerator, :type => :generator do
   # Tell generator where to put its output
-  destination File.expand_path('../tmp', __FILE__)
+  destination Dir.mktmpdir
   before { prepare_destination }
 
   describe 'generator output' do