overlay: sync with the main profile


git-svn-id: http://pentoo.googlecode.com/svn@5901 04556701-5d27-2e10-b29c-201e0903c0fa
pentoo-radio: new 'mono' use flag, enabled in amd64 profile only


git-svn-id: http://pentoo.googlecode.com/svn@5902 04556701-5d27-2e10-b29c-201e0903c0fa