CentOS 6.7: fix the build failure due to the lack of memory
CentOS 6.7: fix the build failure due to the lack of memory

See GH-2

kaorimatz/packer-templates,wporter82/packer-templates,sachalin/packer_centos,kaorimatz/packer-templates,reallyenglish/packer-templates,reallyenglish/packer-templates,sachalin/packer_centos,wporter82/packer-templates