Add wikimedia commons tileset by Cangjie6

[5zlotych]

All the tiles are licensed under CC BY 4.0
Pretty much all the different tiles are present in this tileset, this includes red 1/3/5/7/9, haku pocchi and tiles from other mahjong variants.
https://en.wikipedia.org/wiki/Mahjong_tiles

[m4tx]

Perhaps a duplicate of m4tx/riichi-hand-rs#24?

[5zlotych]

True, however with this set it's possible to support other red tiles not supported in the generator.

[marcinkurek]

It would be interesting to see these laid out with some negative right margin to bring them closer together.

When doing that, the black outline could also be added in post-processing of the merged image instead of each individual tile, so it doesn't overlap the tile to the left. This would require messing with the images though.