Centralize common basebox settings
[centos-5.8-i386] Update location of epel-release package
[centos-5.8-i386] Ensure rubygems is installed
[centos-5.8-i386] use vbox iso from veewee copy
[centos-5.8-i386] bump version of install mirror url
[centos-5.8-i386] Use common settings for centos basebox def
Update centos 5 box template name