The Tarsnap module is now far more flexible, allowing individual
archives with individual options to be specified at will, allowing
granular backup schedules, etc.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
