Add configurations to allow the use of local CLI Waifu2x

[bajuwa]

Current options for local CLI waifu to try to support:

• Waifu2x Vulkan is a windows exe based program that is triggered via command line and does not require the usual nvidia graphics card setup
  repo: https://github.com/nihui/waifu2x-ncnn-vulkan
• Also consider the mac version (which has the same key CLI argument flags):
  repo: https://github.com/imxieyi/waifu2x-mac
• Any options for the Nvidia/cuda version(s)?

[bajuwa]

Testing with vulkan:

Q: test to see if it's quicker to run waifu on the original input images prior to compilation or the final compiled pages

A: With batch it's similar time, but batch has buggy behaviour for vulkan. With individual files the opening/closing of vulkan is time consuming and results it much more time needed for running on input images.

Q: try to find a good way to set up these configurations so it's the most reusable....

A: choosing 'working directory' and 'command string' with format seems to be reusable enough? though not particular user friendly