Vagrant: Add suse64
Vagrant: Rename boxes to names that are easier to remember (for me)

Version details can still be seen by looking at the Vagrantfile URLs.
Replace FreeImage by libpng

FreeImage did not respect the color masks, was unnecessary overhead, and
isn't in Ubuntu's and Arch's standard repositories, so packaging should
be easier now ;-)
GNUInstallDirs.cmake isn't used any more

And old CMake versions don't have it.
Version 0.3.3, quickfixes for better packaging