Log Message:
graphics/wallust: update to 2.7.1

Changes from 2.7.0 (won't have a release)

 - new colorspace: labfast, ignores floating points to be faster at the
 - cost of precision
 - new backend: fastresize, uses SIMD methods but it fails (for some
   reason) on some images in which usual resized doesn't.
 - new flag: -T/--skip_templates
 - improve overall colorpsaces (lab, labmixed) (74184f0de5)
     - Default to delta_1994 allowing faster runtimes (e0549c1afb)
     - Make the darkest and lighest value 0.3 times the threshold,
       much more better color selection, avoiding plain dark or
       white ones
     - Use generics to encourage more colorspaces
 - add some benches
 - update dependencies (aae66574fa)
 - Config File: Now it's allowed using lab-mixed or labmixed (same
   with hard-dark, fast-resize and other two word methods)
 - overall code improvements (refactors, PathBuf instead of String,
   slices over &Vec<>, ..)