include a more recent hplip version in Luna

[swizzle]

Could the elementaryOS luna release eventually use the hplip version 3.12.6 it is required for my new hp printer. In the repositories the version 3.12.2 is avaliable which doesn't work with my printer.

I tried to update the hplip with the https://launchpad.net/~hplip-isv/+archive/ppa but it doesn't work with ubuntu 12.04 or higher.
So it doesn't work on Luna neither.

I also tried to install it manually but that also failed. I got odd errors.

For a better out of the box user-experience a more recent hplip version should be included.