Add integration test for CentOS 6.3

Use official CentOS 6 AMI:
  http://wiki.centos.org/Cloud/AWS

The image has iptables firewall enabled that only allow SSH connections
in and thus makes the Apache cookbook test to fail. So we just shut down
the whole firewall.

Manifest.txt

@@ -39,7 +39,8 @@ test/integration/cases/cache_path_usage.rb
 test/integration/cases/empty_cook.rb
 test/integration/cases/encrypted_data_bag.rb
 test/integration/cases/knife_bootstrap.rb
-test/integration/centos5_6_test.rb
+test/integration/centos5_8_test.rb
+test/integration/centos6_3_test.rb
 test/integration/debian6_bootstrap_test.rb
 test/integration/debian7_knife_bootstrap_test.rb
 test/integration/gentoo2011_test.rb

test/integration/centos6_3_test.rb

@@ -0,0 +1,24 @@
+require 'integration_helper'
+
+class Centos6_3Test < IntegrationTest
+  def user
+    "root"
+  end
+
+  def image_id
+    "ami-86e15bef"
+  end
+
+  def prepare_server
+    disable_firewall
+    super
+  end
+
+  def disable_firewall
+    system "ssh #{connection_string} service iptables stop >> #{log_file}"
+  end
+
+  include EmptyCook
+  include Apache2Cook
+  include EncryptedDataBag
+end