Local customisations for centos-7.0

* use my local timezone and mirrors
* add postprocessor configuration to build boxes for vagrant-libvirt (note:
  not compatible with stock Packer)
* misc other personalisations to kickstart
Local customisations for ubuntu-14.04

* add tty console configuration for use with kvm/libvirt
* add cloud-init configuration
* disable IPv6 privacy addresses
* add qemu build and vagrant post-processor (note: not compatible with stock
  Packer)
* use my local timezone and mirrors in preseed file
* update to 14.04.1
* misc other personal customisations