Progrimage 0.17

• Added .ico support.
  • Can now save and load .ico files.
  • Saving creates an .ico file with sizes 16, 32, 48, 64, 128, and 256.
  • Loading tries to load the largest size.
• Only use nearest neighbor upscaling when sufficiently zoomed into the canvas. This should make the image look much better when only zoomed in a little bit.
• Updated dependencies.