Setup on Debian broken due to missing $lts param

Added $lts parameter to Debian manifest and used it via ```$::jenkins::repo::lts```. If this has any other consequences for puppet dynamic scoping changes in version 3 I'm not sure about. At least the manifest worked on Ubuntu 12.10 and 12.04 using puppet 2.7.x and 3.0.2 in Vagrant boxes and real hardware. ;)

Also refs #45 and refs #42