LTSP daily image tarballs

Upstream ltsp.org is switching to launchpad. A bzr maintainable packagelist (similar to the ubuntu seeds in an easy wiki format) has to be created to enable the ltsp.org maintainers to select packages to be included in a daily build of a ltsp thin client image which users can download and just unpack to get a ltsp thin client environment. The building of the tar.gz packages for the different arches should happen on a fixed schedule but it also should be possible to be done on demand to test immediate changes.