Arch Linux templates update

I had tried to build an Arch box but found that it hung when the postinstall script tried to reboot. Also, guest additions installation did not seem to work. So I ended up updating the templates.

The i686 template will be almost exactly the same as the x86_64 one, including the README, except for one difference:

    --- a/templates/archlinux-x86-64/definition.rb
    +++ b/templates/archlinux-i386/definition.rb
    @@ -14,7 +14,7 @@
       :disk_size   => '10140',
       :disk_format => 'VDI',
       :hostiocache => 'off',
    -  :os_type_id  => 'ArchLinux_64',
    +  :os_type_id  => 'ArchLinux',
       :iso_file    => iso,
       :iso_src     => "#{iso_mirror}/#{iso}",
       :iso_md5     => iso_md5,

Is there a way to share the postinstall scripts and definition so `veewee vbox define` gets all the necessary files? If not, I can copy over the files for the i686 template.